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Conditional Statement – Definition, Truth Table, Examples, FAQs

What is a conditional statement, how to write a conditional statement, what is a biconditional statement, solved examples on conditional statements, practice problems on conditional statements, frequently asked questions about conditional statements.

A conditional statement is a statement that is written in the “If p, then q” format. Here, the statement p is called the hypothesis and q is called the conclusion. It is a fundamental concept in logic and mathematics. 

Conditional statement symbol :  p → q

A conditional statement consists of two parts.

  • The “if” clause, which presents a condition or hypothesis.
  • The “then” clause, which indicates the consequence or result that follows if the condition is true. 

Example : If you brush your teeth, then you won’t get cavities.

Hypothesis (Condition): If you brush your teeth

Conclusion (Consequence): then you won’t get cavities 

Conditional statement

Conditional Statement: Definition

A conditional statement is characterized by the presence of “if” as an antecedent and “then” as a consequent. A conditional statement, also known as an “if-then” statement consists of two parts:

  • The “if” clause (hypothesis): This part presents a condition, situation, or assertion. It is the initial condition that is being considered.
  • The “then” clause (conclusion): This part indicates the consequence, result, or action that will occur if the condition presented in the “if” clause is true or satisfied. 

Related Worksheets

Complete the Statements Using Addition Sentence Worksheet

Representation of Conditional Statement

The conditional statement of the form ‘If p, then q” is represented as p → q. 

It is pronounced as “p implies q.”

Different ways to express a conditional statement are:

  • p implies q
  • p is sufficient for q
  • q is necessary for p

Parts of a Conditional Statement

There are two parts of conditional statements, hypothesis and conclusion. The hypothesis or condition will begin with the “if” part, and the conclusion or action will begin with the “then” part. A conditional statement is also called “implication.”

Conditional Statements Examples:

Example 1: If it is Sunday, then you can go to play. 

Hypothesis: If it is Sunday

Conclusion: then you can go to play. 

Example 2: If you eat all vegetables, then you can have the dessert.

Condition: If you eat all vegetables

Conclusion: then you can have the dessert 

To form a conditional statement, follow these concise steps:

Step 1 : Identify the condition (antecedent or “if” part) and the consequence (consequent or “then” part) of the statement.

Step 2 : Use the “if… then…” structure to connect the condition and consequence.

Step 3 : Ensure the statement expresses a logical relationship where the condition leads to the consequence.

Example 1 : “If you study (condition), then you will pass the exam (consequence).” 

This conditional statement asserts that studying leads to passing the exam. If you study (condition is true), then you will pass the exam (consequence is also true).

Example 2 : If you arrange the numbers from smallest to largest, then you will have an ascending order.

Hypothesis: If you arrange the numbers from smallest to largest

Conclusion: then you will have an ascending order

Truth Table for Conditional Statement

The truth table for a conditional statement is a table used in logic to explore the relationship between the truth values of two statements. It lists all possible combinations of truth values for “p” and “q” and determines whether the conditional statement is true or false for each combination. 

The truth value of p → q is false only when p is true and q is False. 

If the condition is false, the consequence doesn’t affect the truth of the conditional; it’s always true.

In all the other cases, it is true.

The truth table is helpful in the analysis of possible combinations of truth values for hypothesis or condition and conclusion or action. It is useful to understand the presence of truth or false statements. 

Converse, Inverse, and Contrapositive

The converse, inverse, and contrapositive are three related conditional statements that are derived from an original conditional statement “p → q.” 

Consider a conditional statement: If I run, then I feel great.

  • Converse: 

The converse of “p → q” is “q → p.” It reverses the order of the original statement. While the original statement says “if p, then q,” the converse says “if q, then p.” 

Converse: If I feel great, then I run.

  • Inverse: 

The inverse of “p → q” is “~p → ~q,” where “” denotes negation (opposite). It negates both the antecedent (p) and the consequent (q). So, if the original statement says “if p, then q,” the inverse says “if not p, then not q.”

Inverse : If I don’t run, then I don’t feel great.

  • Contrapositive: 

The contrapositive of “p → q” is “~q → ~p.” It reverses the order and also negates both the statements. So, if the original statement says “if p, then q,” the contrapositive says “if not q, then not p.”

Contrapositive: If I don’t feel great, then I don’t run.

A biconditional statement is a type of compound statement in logic that expresses a bidirectional or two-way relationship between two statements. It asserts that “p” is true if and only if “q” is true, and vice versa. In symbolic notation, a biconditional statement is represented as “p ⟺ q.”

In simpler terms, a biconditional statement means that the truth of “p” and “q” are interdependent. 

If “p” is true, then “q” must also be true, and if “q” is true, then “p” must be true. Conversely, if “p” is false, then “q” must be false, and if “q” is false, then “p” must be false. 

Biconditional statements are often used to express equality, equivalence, or conditions where two statements are mutually dependent for their truth values. 

Examples : 

  • I will stop my bike if and only if the traffic light is red.  
  • I will stay if and only if you play my favorite song.

Facts about Conditional Statements

  • The negation of a conditional statement “p → q” is expressed as “p and not q.” It is denoted as “𝑝 ∧ ∼𝑞.” 
  • The conditional statement is not logically equivalent to its converse and inverse.
  • The conditional statement is logically equivalent to its contrapositive. 
  • Thus, we can write p → q ∼q → ∼p

In this article, we learned about the fundamentals of conditional statements in mathematical logic, including their structure, parts, truth tables, conditional logic examples, and various related concepts. Understanding conditional statements is key to logical reasoning and problem-solving. Now, let’s solve a few examples and practice MCQs for better comprehension.

Example 1: Identify the hypothesis and conclusion. 

If you sing, then I will dance.

Solution : 

Given statement: If you sing, then I will dance.

Here, the antecedent or the hypothesis is “if you sing.”

The conclusion is “then I will dance.”

Example 2: State the converse of the statement: “If the switch is off, then the machine won’t work.” 

Here, p: The switch is off

q: The machine won’t work.

The conditional statement can be denoted as p → q.

Converse of p → q is written by reversing the order of p and q in the original statement.

Converse of  p → q is q → p.

Converse of  p → q: q → p: If the machine won’t work, then the switch is off.

Example 3: What is the truth value of the given conditional statement? 

If 2+2=5 , then pigs can fly.

Solution:  

q: Pigs can fly.

The statement p is false. Now regardless of the truth value of statement q, the overall statement will be true. 

F → F = T

Hence, the truth value of the statement is true. 

Conditional Statement - Definition, Truth Table, Examples, FAQs

Attend this quiz & Test your knowledge.

What is the antecedent in the given conditional statement? If it’s sunny, then I’ll go to the beach.

A conditional statement can be expressed as, what is the converse of “a → b”, when the antecedent is true and the consequent is false, the conditional statement is.

What is the meaning of conditional statements?

Conditional statements, also known as “if-then” statements, express a cause-and-effect or logical relationship between two propositions.

When does the truth value of a conditional statement is F?

A conditional statement is considered false when the antecedent is true and the consequent is false.

What is the contrapositive of a conditional statement?

The contrapositive reverses the order of the statements and also negates both the statements. It is equivalent in truth value to the original statement.

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3.3: Truth Tables- Conditional, Biconditional

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Conditional

A conditional is a logical compound statement in which a statement \(p\), called the hypothesis, implies a statement \(q\), called the conclusion.

A conditional is written as \(p \rightarrow q\) and is translated as "if \(p\), then \(q\)".

The English statement “If it is raining, then there are clouds is the sky” is a conditional statement. It makes sense because if the hypothesis “it is raining” is true, then the conclusion “there are clouds in the sky” must also be true.

Notice that the statement tells us nothing of what to expect if it is not raining; there might be clouds in the sky, or there might not. If the hypothesis is false, then the conclusion becomes irrelevant.

Suppose you order a team jersey online on Tuesday and want to receive it by Friday so you can wear it to Saturday’s game. The website says that if you pay for expedited shipping, you will receive the jersey by Friday. In what situation is the website telling a lie?

There are four possible outcomes:

  • You pay for expedited shipping and receive the jersey by Friday
  • You pay for expedited shipping and don’t receive the jersey by Friday
  • You don’t pay for expedited shipping and receive the jersey by Friday
  • You don’t pay for expedited shipping and don’t receive the jersey by Friday

Only one of these outcomes proves that the website was lying: the second outcome in which you pay for expedited shipping but don’t receive the jersey by Friday. The first outcome is exactly what was promised, so there’s no problem with that. The third outcome is not a lie because the website never said what would happen if you didn’t pay for expedited shipping; maybe the jersey would arrive by Friday whether you paid for expedited shipping or not. The fourth outcome is not a lie because, again, the website didn’t make any promises about when the jersey would arrive if you didn’t pay for expedited shipping.

It may seem strange that the third outcome in the previous example, in which the first part is false but the second part is true, is not a lie. Remember, though, that if the hypothesis is false, we cannot make any judgment about the conclusion. The website never said that paying for expedited shipping was the only way to receive the jersey by Friday.

A friend tells you “If you upload that picture to Facebook, you’ll lose your job.” Under what conditions can you say that your friend was wrong?

  • You upload the picture and lose your job
  • You upload the picture and don’t lose your job
  • You don’t upload the picture and lose your job
  • You don’t upload the picture and don’t lose your job

There is only one possible case in which you can say your friend was wrong: the second outcome in which you upload the picture but still keep your job. In the last two cases, your friend didn’t say anything about what would happen if you didn’t upload the picture, so you can’t say that their statement was wrong. Even if you didn’t upload the picture and lost your job anyway, your friend never said that you were guaranteed to keep your job if you didn’t upload the picture; you might lose your job for missing a shift or punching your boss instead.

Truth Table for the Conditional

\(\begin{array}{|c|c|c|} \hline p & q & p \rightarrow q \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{T} \\ \hline \end{array}\)

Again, if the hypothesis \(p\) is false, we cannot prove that the statement is a lie, so the result of the third and fourth rows is true.

Construct a truth table for the statement \((m \wedge \sim p) \rightarrow r\)

We start by constructing a truth table with 8 rows to cover all possible scenarios. Next, we can focus on the hypothesis, \(m \wedge \sim p\).

\(\begin{array}{|c|c|c|} \hline m & p & r \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{F} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{F} \\ \hline \end{array}\)

\(\begin{array}{|c|c|c|c|} \hline m & p & r & \sim p \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{F} \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{T} \\ \hline \end{array}\)

\(\begin{array}{|c|c|c|c|c|} \hline m & p & r & \sim p & m \wedge \sim p \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{F} \\ \hline \end{array}\)

Now we can create a column for the conditional. Because it can be confusing to keep track of all the Ts and \(\mathrm{Fs}\), why don't we copy the column for \(r\) to the right of the column for \(m \wedge \sim p\) ? This makes it a lot easier to read the conditional from left to right.

\(\begin{array}{|c|c|c|c|c|c|c|} \hline m & p & r & \sim p & m \wedge \sim p & r & (m \wedge \sim p) \rightarrow r \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{T} \\ \hline \end{array}\)

When \(m\) is true, \(p\) is false, and \(r\) is false- -the fourth row of the table-then the hypothesis \(m \wedge \sim p\) will be true but the conclusion false, resulting in an invalid conditional; every other case gives a valid conditional.

If you want a real-life situation that could be modeled by \((m \wedge \sim p) \rightarrow r\), consider this: let \(m=\) we order meatballs, \(p=\) we order pasta, and \(r=\) Rob is happy. The statement \((m \wedge \sim p) \rightarrow r\) is "if we order meatballs and don't order pasta, then Rob is happy". If \(m\) is true (we order meatballs), \(p\) is false (we don't order pasta), and \(r\) is false (Rob is not happy), then the statement is false, because we satisfied the hypothesis but Rob did not satisfy the conclusion.

For any conditional, there are three related statements, the converse, the inverse, and the contrapositive.

Derived Forms of a Conditional

The original conditional is \(\quad\) "if \(p,\) then \(q^{\prime \prime} \quad p \rightarrow q\)

The converse is \(\quad\) "if \(q,\) then \(p^{\prime \prime} \quad q \rightarrow p\)

The inverse is \(\quad\) "if not \(p,\) then not \(q^{\prime \prime} \quad \sim p \rightarrow \sim q\)

The contrapositive is "if not \(q,\) then not \(p^{\prime \prime} \quad \sim q \rightarrow \sim p\)

Consider again the conditional “If it is raining, then there are clouds in the sky.” It seems reasonable to assume that this is true.

The converse would be “If there are clouds in the sky, then it is raining.” This is not always true.

The inverse would be “If it is not raining, then there are not clouds in the sky.” Likewise, this is not always true.

The contrapositive would be “If there are not clouds in the sky, then it is not raining.” This statement is true, and is equivalent to the original conditional.

Looking at truth tables, we can see that the original conditional and the contrapositive are logically equivalent, and that the converse and inverse are logically equivalent.

clipboard_e4fc512ef5eaeb010f3e7328168fcef19.png

Equivalence

A conditional statement and its contrapositive are logically equivalent.

The converse and inverse of a conditional statement are logically equivalent.

In other words, the original statement and the contrapositive must agree with each other; they must both be true, or they must both be false. Similarly, the converse and the inverse must agree with each other; they must both be true, or they must both be false.

We typically represent the conditional using the words, "if ..., then ...," but there are other ways this logical connective can be represented in English. Consider the conditional from Example 5: "If it is raining, then there are clouds in the sky." We could equivalently write, "It is raining only if there are clouds in the sky." You can probably imagine how these two statements are saying the same thing - whenever it's raining outside, it is a safe conclusion there are clouds in the sky as well. Some other wordings that communicate the same information use either "sufficient" or "necessary." For example, "Raining is a sufficient condition for it to be cloudy," and "Being cloudy is a necessary condition for it to be raining." Here is a table summarizing the different wordings.

Different Wordings of the Conditional

The following statements are equivalent:

  • If \(p\), then \(q\).
  • \(q\) only if \(p\).
  • \(p\) is sufficient for \(q\).
  • \(q\) is necessary for \(p\).

In everyday life, we often have a stronger meaning in mind when we use a conditional statement. Consider “If you submit your hours today, then you will be paid next Friday.” What the payroll rep really means is “If you submit your hours today, then you will be paid next Friday, and if you don’t submit your hours today, then you won’t be paid next Friday.” The conditional statement if t , then p also includes the inverse of the statement: if not t , then not p . A more compact way to express this statement is “You will be paid next Friday if and only if you submit your timesheet today.” A statement of this form is called a biconditional .

Biconditional

A biconditional is a logical conditional statement in which the hypothesis and conclusion are interchangeable.

A biconditional is written as \(p \leftrightarrow q\) and is translated as " \(p\) if and only if \(q^{\prime \prime}\).

Because a biconditional statement \(p \leftrightarrow q\) is equivalent to \((p \rightarrow q) \wedge(q \rightarrow p),\) we may think of it as a conditional statement combined with its converse: if \(p\), then \(q\) and if \(q\), then \(p\). The double-headed arrow shows that the conditional statement goes from left to right and from right to left. A biconditional is considered true as long as the hypothesis and the conclusion have the same truth value; that is, they are either both true or both false.

Truth Table for the Biconditional

\(\begin{array}{|c|c|c|} \hline p & q & p \leftrightarrow q \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{T} \\ \hline \end{array}\)

Notice that the fourth row, where both components are false, is true; if you don’t submit your timesheet and you don’t get paid, the person from payroll told you the truth.

Suppose this statement is true: “The garbage truck comes down my street if and only if it is Thursday morning.” Which of the following statements could be true?

  • It is noon on Thursday and the garbage truck did not come down my street this morning.
  • It is Monday and the garbage truck is coming down my street.
  • It is Wednesday at 11:59PM and the garbage truck did not come down my street today.
  • This cannot be true. This is like the second row of the truth table; it is true that I just experienced Thursday morning, but it is false that the garbage truck came.
  • This cannot be true. This is like the third row of the truth table; it is false that it is Thursday, but it is true that the garbage truck came.
  • This could be true. This is like the fourth row of the truth table; it is false that it is Thursday, but it is also false that the garbage truck came, so everything worked out like it should.

Try it Now 1

Suppose this statement is true: “I wear my running shoes if and only if I am exercising.” Determine whether each of the following statements must be true or false.

  • I am exercising and I am not wearing my running shoes.
  • I am wearing my running shoes and I am not exercising.
  • I am not exercising and I am not wearing my running shoes.

Choices a & b are false; c is true.

Create a truth table for the statement \((A \vee B) \leftrightarrow \sim C\)

Whenever we have three component statements, we start by listing all the possible truth value combinations for \(A, B,\) and \(C .\) After creating those three columns, we can create a fourth column for the hypothesis, \(A \vee B\). Now we will temporarily ignore the column for \(C\) and focus on \(A\) and \(B\), writing the truth values for \(A \vee B\).

\(\begin{array}{|c|c|c|} \hline A & B & C \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{F} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{F} \\ \hline \end{array}\)

\(\begin{array}{|c|c|c|c|} \hline A & B & C & A \vee B \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{F} \\ \hline \end{array}\)

Next we can create a column for the negation of \(C\). (Ignore the \(A \vee B\) column and simply negate the values in the \(C\) column.)

\(\begin{array}{|c|c|c|c|c|} \hline A & B & C & A \vee B & \sim C \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{F} \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{F} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{T} \\ \hline \end{array}\)

Finally, we find the truth values of \((A \vee B) \leftrightarrow \sim C\). Remember, a biconditional is true when the truth value of the two parts match, but it is false when the truth values do not match.

\(\begin{array}{|c|c|c|c|c|c|} \hline A & B & C & A \vee B & \sim C & (A \vee B) \leftrightarrow \sim C \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{F} & \mathrm{F} \\ \hline \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{T} & \mathrm{T} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{F} & \mathrm{F} & \mathrm{T} \\ \hline \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{F} & \mathrm{T} & \mathrm{F} \\ \hline \end{array}\)

To illustrate this situation, suppose your boss needs you to do either project \(A\) or project \(B\) (or both, if you have the time). If you do one of the projects, you will not get a crummy review ( \(C\) is for crummy). So \((A \vee B) \leftrightarrow \sim C\) means "You will not get a crummy review if and only if you do project \(A\) or project \(B\)." Looking at a few of the rows of the truth table, we can see how this works out. In the first row, \(A, B,\) and \(C\) are all true: you did both projects and got a crummy review, which is not what your boss told you would happen! That is why the final result of the first row is false. In the fourth row, \(A\) is true, \(B\) is false, and \(C\) is false: you did project \(A\) and did not get a crummy review. This is what your boss said would happen, so the final result of this row is true. And in the eighth row, \(A, B\), and \(C\) are all false: you didn't do either project and did not get a crummy review. This is not what your boss said would happen, so the final result of this row is false. (Even though you may be happy that your boss didn't follow through on the threat, the truth table shows that your boss lied about what would happen.)

Conditional Statement

A conditional statement is a part of mathematical reasoning which is a critical skill that enables students to analyze a given hypothesis without any reference to a particular context or meaning. In layman words, when a scientific inquiry or statement is examined, the reasoning is not based on an individual's opinion. Derivations and proofs need a factual and scientific basis. 

Mathematical critical thinking and logical reasoning are important skills that are required to solve maths reasoning questions.

If and Then  conditional image

In this mini-lesson, we will explore the world of conditional statements. We will walk through the answers to the questions like what is meant by a conditional statement, what are the parts of a conditional statement, and how to create conditional statements along with solved examples and interactive questions.

Lesson Plan  

What is meant by a conditional statement.

A statement that is of the form "If p, then q" is a conditional statement. Here 'p' refers to 'hypothesis' and 'q' refers to 'conclusion'.

For example, "If Cliff is thirsty, then she drinks water."

conditional statement

This is a conditional statement. It is also called an implication.

'\(\rightarrow\)' is the symbol used to represent the relation between two statements. For example, A\(\rightarrow\)B. It is known as the logical connector. It can be read as A implies B. 

Here are two more conditional statement examples

Example 1: If a number is divisible by 4, then it is divisible by 2.

Example 2: If today is Monday, then yesterday was Sunday.

What Are the Parts of a Conditional Statement?

Hypothesis (if) and Conclusion (then) are the two main parts that form a conditional statement.

Let us consider the above-stated example to understand the parts of a conditional statement.

Conditional Statement : If today is Monday, then yesterday was Sunday.

Hypothesis : "If today is Monday."

Conclusion : "Then yesterday was Sunday."

On interchanging the form of statement the relationship gets changed.

To check whether the statement is true or false here, we have subsequent parts of a conditional statement. They are:

  • Contrapositive

Biconditional Statement

Let us consider hypothesis as statement A and Conclusion as statement B.

Following are the observations made:

Conditions of conditional statement

Converse of Statement

When hypothesis and conclusion are switched or interchanged, it is termed as converse statement . For example,

Conditional Statement : “If today is Monday, then yesterday was Sunday.”

Hypothesis : “If today is Monday”

Converse : “If yesterday was Sunday, then today is Monday.”

Here the conditional statement logic is, If B, then A (B → A)

Inverse of Statement

When both the hypothesis and conclusion of the conditional statement are negative, it is termed as an inverse of the statement. For example,

Conditional Statement: “If today is Monday, then yesterday was Sunday”.

Inverse : “If today is not Monday, then yesterday was not Sunday.”

Here the conditional statement logic is, If not A, then not B (~A → ~B)

Contrapositive Statement

When the hypothesis and conclusion are negative and simultaneously interchanged, then the statement is contrapositive. For example,

Contrapositive: “If yesterday was not Sunday, then today is not Monday”

Here the conditional statement logic is, if not B, then not A (~B → ~A)

The statement is a biconditional statement when a statement satisfies both the conditions as true, being conditional and converse at the same time. For example,

Biconditional : “Today is Monday if and only if yesterday was Sunday.”

Here the conditional statement logic is, A if and only if B (A ↔ B)

How to Create Conditional Statements?

Here, the point to be kept in mind is that the 'If' and 'then' part must be true.

If a number is a perfect square , then it is even.

  • 'If' part is a number that is a perfect square.

Think of 4 which is a perfect square.

This has become true.

  • The 'then' part is that the number should be even. 4 is even.

This has also become true. 

Thus, we have set up a conditional statement.

Let us hypothetically consider two statements, statement A and statement B. Observe the truth table for the statements:

According to the table, only if the hypothesis (A) is true and the conclusion (B) is false then, A → B will be false, or else A → B will be true for all other conditions.

tips and tricks

  • A sentence needs to be either true or false, but not both, to be considered as a mathematically accepted statement.
  • Any sentence which is either imperative or interrogative or exclamatory cannot be considered a mathematically validated statement. 
  • A sentence containing one or many variables is termed as an open statement. An open statement can become a statement if the variables present in the sentence are replaced by definite values.

Solved Examples

Let us have a look at a few solved examples on conditional statements.

Identify the types of conditional statements.

There are four types of conditional statements:

  • If condition
  • If-else condition
  • Nested if-else
  • If-else ladder.

Ray tells "If the perimeter of a rectangle is 14, then its area is 10."

Which of the following could be the counterexamples? Justify your decision.

a) A rectangle with sides measuring 2 and 5

b) A rectangle with sides measuring 10 and 1

c) A rectangle with sides measuring 1 and 5

d) A rectangle with sides measuring 4 and 3

a) Rectangle with sides 2 and 5: Perimeter = 14 and area = 10

Both 'if' and 'then' are true.

b) Rectangle with sides 10 and 1: Perimeter = 22 and area = 10

'If' is false and 'then' is true.

c) Rectangle with sides 1 and 5: Perimeter = 12 and area = 5

Both 'if' and 'then' are false.

d) Rectangle with sides 4 and 3: Perimeter = 14 and area = 12

'If' is true and 'then' is false.

Joe examined the set of numbers {16, 27, 24} to check if they are the multiples of 3. He claimed that they are divisible by 9. Do you agree or disagree? Justify your answer.

Conditional statement : If a number is a multiple of 3, then it is divisible by 9.

Let us find whether the conditions are true or false.

a) 16 is not a multiple of 3. Thus, the condition is false. 

16 is not divisible by 9. Thus, the conclusion is false. 

b) 27 is a multiple of 3. Thus, the condition is true.

27 is divisible by 9. Thus, the conclusion is true. 

c) 24 is a multiple of 3. Thus the condition is true.

24 is not divisible by 9. Thus the conclusion is false.

Write the converse, inverse, and contrapositive statement for the following conditional statement. 

If you study well, then you will pass the exam.

The given statement is - If you study well, then you will pass the exam.

It is of the form, "If p, then q"

The converse statement is, "You will pass the exam if you study well" (if q, then p).

The inverse statement is, "If you do not study well then you will not pass the exam" (if not p, then not q).

The contrapositive statement is, "If you did not pass the exam, then you did not study well" (if not q, then not p).

Interactive Questions

Here are a few activities for you to practice. Select/Type your answer and click the "Check Answer" button to see the result.

Challenge your math skills

Let's Summarize

The mini-lesson targeted the fascinating concept of the conditional statement. The math journey around conditional statements started with what a student already knew and went on to creatively crafting a fresh concept in the young minds. Done in a way that not only it is relatable and easy to grasp, but also will stay with them forever.

About Cuemath

At  Cuemath , our team of math experts is dedicated to making learning fun for our favorite readers, the students!

Through an interactive and engaging learning-teaching-learning approach, the teachers explore all angles of a topic.

Be it worksheets, online classes, doubt sessions, or any other form of relation, it’s the logical thinking and smart learning approach that we, at Cuemath, believe in.

FAQs on Conditional Statement

1. what is the most common conditional statement.

'If and then' is the most commonly used conditional statement.

2. When do you use a conditional statement?

Conditional statements are used to justify the given condition or two statements as true or false.

3. What is if and if-else statement?

If is used when a specified condition is true. If-else is used when a particular specified condition is not satisfying and is false.

4. What is the symbol for a conditional statement?

'\(\rightarrow\)' is the symbol used to represent the relation between two statements. For example, A\(\rightarrow\)B. It is known as the logical connector. It can be read as A implies B.

5. What is the Contrapositive of a conditional statement?

If not B, then not A (~B → ~A)

6. What is a universal conditional statement?

Conditional statements are those statements where a hypothesis is followed by a conclusion. It is also known as an " If-then" statement. If the hypothesis is true and the conclusion is false, then the conditional statement is false. Likewise, if the hypothesis is false the whole statement is false. Conditional statements are also termed as implications.

Conditional Statement: If today is Monday, then yesterday was Sunday

Hypothesis: "If today is Monday."

Conclusion: "Then yesterday was Sunday."

If A, then B (A → B)

  • Live one on one classroom and doubt clearing
  • Practice worksheets in and after class for conceptual clarity
  • Personalized curriculum to keep up with school

2.4 Truth Tables for the Conditional and Biconditional

Learning objectives.

After completing this section, you should be able to:

  • Use and apply the conditional to construct a truth table.
  • Use and apply the biconditional to construct a truth table.
  • Use truth tables to determine the validity of conditional and biconditional statements.

Computer languages use if-then or if-then-else statements as decision statements:

  • If the hypothesis is true, then do something.
  • Or, if the hypothesis is true, then do something; else do something else.

For example, the following representation of computer code creates an if-then-else decision statement:

Check value of variable i i .

If i < 1 i < 1 , then print "Hello, World!" else print "Goodbye".

In this imaginary program, the if-then statement evaluates and acts on the value of the variable i i . For instance, if i = 0 i = 0 , the program would consider the statement i < 1 i < 1 as true and “Hello, World!” would appear on the computer screen. If instead, i = 3 i = 3 , the program would consider the statement i < 1 i < 1 as false (because 3 is greater than 1), and print “Goodbye” on the screen.

In this section, we will apply similar reasoning without the use of computer programs.

People in Mathematics

The Countess of Lovelace, Ada Lovelace, is credited with writing the first computer program. She wrote an algorithm to work with Charles Babbage’s Analytical Engine that could compute the Bernoulli numbers in 1843. In doing so, she became the first person to write a program for a machine that would produce more than just a simple calculation. The computer programming language ADA is named after her.

Reference: Posamentier, Alfred and Spreitzer Christian, “Chapter 34 Ada Lovelace: English (1815-1852)” pp. 272-278, Math Makers: The Lives and Works of 50 Famous Mathematicians , Prometheus Books, 2019.

Use and Apply the Conditional to Construct a Truth Table

A conditional is a logical statement of the form if p p , then q q . The conditional statement in logic is a promise or contract. The only time the conditional, p → q , p → q , is false is when the contract or promise is broken.

For example, consider the following scenario. A child’s parent says, “If you do your homework, then you can play your video games.” The child really wants to play their video games, so they get started right away, finish within an hour, and then show their parent the completed homework. The parent thanks the child for doing a great job on their homework and allows them to play video games. Both the parent and child are happy. The contract was satisfied; true implies true is true.

Now, suppose the child does not start their homework right away, and then struggles to complete it. They eventually finish and show it to their parent. The parent again thanks the child for completing their homework, but then informs the child that it is too late in the evening to play video games, and that they must begin to get ready for bed. Now, the child is really upset. They held up their part of the contract, but they did not receive the promised reward. The contract was broken; true implies false is false.

So, what happens if the child does not do their homework? In this case, the hypothesis is false. No contract has been entered, therefore, no contract can be broken. If the conclusion is false, the child does not get to play video games and might not be happy, but this outcome is expected because the child did not complete their end of the bargain. They did not complete their homework. False implies false is true. The last option is not as intuitive. If the parent lets the child play video games, even if they did not do their homework, neither parent nor child are going to be upset. False implies true is true.

The truth table for the conditional statement below summarizes these results.

Notice that the only time the conditional statement, p → q , p → q , is false is when the hypothesis, p p , is true and the conclusion, q q , is false.

Logic Part 8: The Conditional and Tautologies

Example 2.18

Constructing truth tables for conditional statements.

Assume both of the following statements are true: p p : My sibling washed the dishes, and q q : My parents paid them $5.00. Create a truth table to determine the truth value of each of the following conditional statements.

  • p → q p → q
  • p → ~ q p → ~ q
  • ~ p → q ~ p → q

Your Turn 2.18

Example 2.19, determining validity of conditional statements.

Construct a truth table to analyze all possible outcomes for each of the following statements then determine whether they are valid.

  • p ∧ q → ~ q p ∧ q → ~ q
  • p → ~ p ∨ q p → ~ p ∨ q

Your Turn 2.19

Use and apply the biconditional to construct a truth table.

The biconditional, p ↔ q p ↔ q , is a two way contract; it is equivalent to the statement ( p → q ) ∧ ( q → p ) . ( p → q ) ∧ ( q → p ) . A biconditional statement, p ↔ q , p ↔ q , is true whenever the truth value of the hypothesis matches the truth value of the conclusion, otherwise it is false.

The truth table for the biconditional is summarized below.

Logic Part 11B: Biconditional and Summary of Truth Value Rules in Logic

Example 2.20

Constructing truth tables for biconditional statements.

Assume both of the following statements are true: p p : The plumber fixed the leak, and q q : The homeowner paid the plumber $150.00. Create a truth table to determine the truth value of each of the following biconditional statements.

  • p ↔ q p ↔ q
  • p ↔ ~ q p ↔ ~ q
  • ~ p ↔ ~ q ~ p ↔ ~ q

Your Turn 2.20

The biconditional, p ↔ q , p ↔ q , is true whenever the truth values of p p and q q match, otherwise it is false.

Logic Part 13: Truth Tables to Determine if Argument is Valid or Invalid

Example 2.21

Determining validity of biconditional statements.

Construct a truth table to analyze all possible outcomes for each of the following statements, then determine whether they are valid.

  • p ∧ q ↔ p ∧ ~ q p ∧ q ↔ p ∧ ~ q
  • p ∨ q ↔ ~ p ∨ q p ∨ q ↔ ~ p ∨ q
  • p → q ↔ ~ q → ~ p p → q ↔ ~ q → ~ p
  • p ∧ q → ~ r ↔ p ∧ q ∧ r p ∧ q → ~ r ↔ p ∧ q ∧ r

Your Turn 2.21

Check your understanding, section 2.4 exercises.

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2.11: If Then Statements

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Hypothesis followed by a conclusion in a conditional statement.

Conditional Statements

A conditional statement (also called an if-then statement ) is a statement with a hypothesis followed by a conclusion . The hypothesis is the first, or “if,” part of a conditional statement. The conclusion is the second, or “then,” part of a conditional statement. The conclusion is the result of a hypothesis.

f-d_4db5d03aa180674c10187c8961dc571238102082156ee867771ecea3+IMAGE_TINY+IMAGE_TINY.png

If-then statements might not always be written in the “if-then” form. Here are some examples of conditional statements:

  • Statement 1: If you work overtime, then you’ll be paid time-and-a-half.
  • Statement 2: I’ll wash the car if the weather is nice.
  • Statement 3: If 2 divides evenly into \(x\), then \(x\) is an even number.
  • Statement 4: I’ll be a millionaire when I win the lottery.
  • Statement 5: All equiangular triangles are equilateral.

Statements 1 and 3 are written in the “if-then” form. The hypothesis of Statement 1 is “you work overtime.” The conclusion is “you’ll be paid time-and-a-half.” Statement 2 has the hypothesis after the conclusion. If the word “if” is in the middle of the statement, then the hypothesis is after it. The statement can be rewritten: If the weather is nice, then I will wash the car. Statement 4 uses the word “when” instead of “if” and is like Statement 2. It can be written: If I win the lottery, then I will be a millionaire. Statement 5 “if” and “then” are not there. It can be rewritten: If a triangle is equiangular, then it is equilateral.

What if you were given a statement like "All squares are rectangles"? How could you determine the hypothesis and conclusion of this statement?

Example \(\PageIndex{1}\)

Determine the hypothesis and conclusion: I'll bring an umbrella if it rains.

Hypothesis: "It rains." Conclusion: "I'll bring an umbrella."

Example \(\PageIndex{2}\)

Determine the hypothesis and conclusion: All right angles are \(90^{\circ}\).

Hypothesis: "An angle is right." Conclusion: "It is \(90^{\circ}\)."

Example \(\PageIndex{3}\)

Use the statement: I will graduate when I pass Calculus.

Rewrite in if-then form and determine the hypothesis and conclusion.

This statement can be rewritten as If I pass Calculus, then I will graduate. The hypothesis is “I pass Calculus,” and the conclusion is “I will graduate.”

Example \(\PageIndex{4}\)

Use the statement: All prime numbers are odd.

Rewrite in if-then form, determine the hypothesis and conclusion, and determine whether this is a true statement.

This statement can be rewritten as If a number is prime, then it is odd. The hypothesis is "a number is prime" and the conclusion is "it is odd". This is not a true statement (remember that not all conditional statements will be true!) since 2 is a prime number but it is not odd.

Example \(\PageIndex{5}\)

Determine the hypothesis and conclusion: Sarah will go to the store if Riley does the laundry.

The statement can be rewritten as "If Riley does the laundry then Sarah will go to the store." The hypothesis is "Riley does the laundry" and the conclusion is "Sarah will go to the store."

Determine the hypothesis and the conclusion for each statement.

  • If 5 divides evenly into \(x\), then \(x\) ends in 0 or 5.
  • If a triangle has three congruent sides, it is an equilateral triangle.
  • Three points are coplanar if they all lie in the same plane.
  • If \(x=3\), then \(x^2=9\).
  • If you take yoga, then you are relaxed.
  • All baseball players wear hats.
  • I'll learn how to drive when I am 16 years old.
  • If you do your homework, then you can watch TV.
  • Alternate interior angles are congruent if lines are parallel.
  • All kids like ice cream.

Additional Resources

Video: If-Then Statements Principles - Basic

Activities: If-Then Statements Discussion Questions

Study Aids: Conditional Statements Study Guide

Practice: If Then Statements

Real World: If Then Statements

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4.8: Conditional/Hypothetical Clauses

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Conditional / Hypothetical Sentences

All conditional / hypothetical sentences consist of a dependent clause beginning with if (or other adverbials of condition) and an independent clause which is a result of the condition or hypothesis. A conditional sentence is one that is real or possibly can happen; a hypothetical sentence is one that is only imaginary - it either will not happen or did not happen.

Class One: Conditional

A.   Present or future situation: True and Real or Possible

If + present tense verb,     will or future implied verb ( c an, might, want, need, etc.)

           Examples:

If my sister visits Seattle, I will take her to Mount Rainier.

If we go there, I want to take a picnic lunch.

B.   General Truth situations, not for a specific time, something is always true and never changes.  It is True and Real or Possible

If + present tense verb,     present tense verb

           Examples:

If plants have good soil and get enough sunlight and water, they always grow well.

If a car runs out of gas, it stops.

C.  Past Situations: True and Completed Actions in the Past

Form:    

If + past tense,   past tense

           Examples:

If my father caught fish, he was happy.

If my grandmother cooked dinner when I was a boy, I always ate a lot.  

D.  Alternate Form for the Present and Future Situations : Should

We can use should in Class One conditional sentences in the present and future  when we are not sure of the condition . Only if the condition happens will the result happen. It gives a feeling of uncertainty (not sure of something).

          Examples:

If you should receive a letter from John, please tell me. Should you receive a letter from John, please let me know.

If you should get stopped by a policeman, you must have your driver's license with you or you will get a ticket. Should you get stopped by a policeman, you must have your driver's license with you or you will get a ticket.

Please note that the Class 3, Class 4, and Class 5 conditional/hypothetical  sentences and exercises will be part of the next book in this series (Book Five).

Exercise 43:  Use a class one conditional sentence to combine these sentences, please.  There are different ways to make these sentences.  Remember that if the IF Clause comes first in a sentence, then you MUST use a comma after the IF CLAUSE.

My son won’t go on a picnic with his friends.  It might rain today. My son won’t go on a picnic with his friends if it rains today.

I will buy a new car.  I refuse to spend a lot of money on a car. I will buy a new car if it doesn’t cost too much.

1.  I might fly back to Providence, R.I. this summer.  I have to find a cheap plane ticket.

2.  The student will come to class tomorrow.  She needs to get a ride from her friend.

3.  I might call my sister this evening.  I have to finish my homework early.

4.  My son eats breakfast.  He must have enough time to eat breakfast.

5.  The student is usually late to class.  When he arrives on time, other students are surprised.

6.  Students study in the library.  They need to use the services of the library.

7.  John will take ENG 102 next quarter.  He must pass ENG 101 this quarter.

8.  People are much happier.  The sun comes out in the summer.

9.  Students can study quietly in the library.  Library patrons are quiet in the library.

10.  My son goes to the piano room.  He wants to practice a piece of music.

11.  The woman gets angry very quickly.  People disagree with her.

12.  You can’t get out of jail.  A judge sentences you to jail.

44:  Complete the following sentences, please.

If I have a headache, ….. If I have a headache, I take three aspirins.

1.  I drink coffee in the afternoon, …..

2.  If it is not raining outside when I get home from work, …..

3.  I watch television if …..

4.  If I finish my homework early, …..

5.  My friend eats in the cafeteria if …..

6.  If I have free time, …..

7.  My dog barks if …..

8.  My back hurts if …..

9.  Children don’t go to school in the morning if …..

10.  If people need extra money, …..

11.  I take medicine if …..

12.  Students usually do their homework if …..

13.  If it is raining outside, …..

Exercise 45:  Complete the following sentences with a future meaning verb, please.

If I have homework this evening, ….. If I have homework this evening, I will do it until it is finished.

1.  If I pass the college’s entrance examination,

2.  If we have an examination next week,

3.  If I have to write a composition for next Monday,

4.  If my friend finishes her homework early,

5.  I will begin college classes next quarter,

6.  If we see each other at the market,

7.  If my friend wins the lottery,

8.  If there is something good on TV tonight,

9.  If I am sick tomorrow morning,

10.  If the gas tank on my car reads close to empty,

11.  If students study grammar,

12.  If some visitors come to Seattle for a visit this summer,

13.  If my friend calls me this weekend,

Exercise 46:  Use a class one conditional sentence in the past situations that were real and did happen, please.

Examples:  If I ate too much candy when I was a boy, I threw up .

If I had to go shopping with my sister and my mother when I was a boy, I wanted to go home right away.

1.  If it snowed a lot, my brother, sister, and I ------------------ (go) sledding.

2.  If the weather was nice after school, I ------------------- (walk) home from school.

3.  If there was a cowboy movie on television, I always ------------------ (watch) it.

4.  If my father took my mother shopping, I -------------------- (stay) in the car with him.

5.  If I got good grades on my report card at school, my parents ------------------- (be) very happy.

6.  If my sister cried when she was a little girl, my father -------------------- (comfort) her.

7.  If we took our lunches to school, we -------------------- (not have to) buy lunch.

8.  If we watched scary movies on TV, we -------------------- (have) a hard time falling asleep.

9.  If it was a holiday, our grandfather always -------------------- (give) us some old coins.

10.  If children were bad in school when I was a boy, teachers -------------------- (hit) them without worrying.

11.  If I bought candy with five cents as a boy, I always -------------------- (get) at least five pieces of candy.

12.  If a student fell asleep in class, the teacher ------------------- (slap) the back of his head to wake him up.

13.  If it was a major holiday, my grandmother and mother ------------------- (cook) both Italian food and American food.

14.  If one of my dogs slept in bed with me, my mother ------------------- (yell) at me and the dog.

15.  If my father had a day off from work, we -------------------- (be) very happy.

16.  If my Uncle Carl took me to a baseball game, I -------------------- (eat) a lot of junk food.

17.  If I caught big fish when I went fishing, I always --------------------- (bring) the fish home to eat for dinner.

Exercise 47:  In a class one conditional, change the IF clause to a SHOULD clause, please.

If I see you in class next Friday, I will be happy. 

Should I see you in class next Friday, I will be happy

1. If you win the lottery, you will become very rich.

2.  If it rains next Friday, you will get wet.

3.  If I catch a cold, I might have a runny nose.

4.  If my car breaks down on my way home, I will call Triple A (AAA) for help.

5.  If my son gets a better job, he will make more money.

6.  If my wife plans a barbecue for dinner this Saturday, I will have to do the cooking.

7.  If the Seattle Mariners ever win the World Series in baseball, I will die a happy man.

8.  If I go to Montreal, Canada, for a vacation, I will visit some of my relatives.

9.  If my son Alex comes home for a visit next year, I will be happy to see him again.

10.  If my son André buys a house, we will give him some furniture.

11.  If it rains hard tomorrow, I won’t be able to work in my garden.

12.  If my sister has enough money, she and her son and daughter-in-law will come to Seattle for a vacation next summer.

Class Two: Hypothetical

A.   Present or Future Situations - will not or are not very likely to occur- Not Real, Not Possible,

                                                                                                         Only Imaginary

If + past tense verb,     would or could   + base form of verb

          Examples:

If I had a million dollars, I would go on a long vacation.

If I played professional baseball, I could make a lot of money.

B.  Verb To Be: Were

In Class Two Conditionals, when you need to use the verb To Be , always use were after if . (This is called the subjunctive.)   

If + subject + were ,     would or could + base form of verb.

  Examples:

If I were a bird, I could fly .

If she were my daughter, I would love her like a father.

C.  Alternate Form for Present Hypothetical Situations: Were    

    Were may be used in place of if to form the Class Two Conditionals; however, this is usually only done in very formal situations.

         Were + noun,     would or could + verb stem

                                           or    

Were + subject + infinitive,     would or could + verb stem

          Examples:    

If you were an American, you would not take ESL classes. Were you an American, you would not take ESL classes.

If I were a woman, I could have a baby. Were I a woman, I could have a baby.

If I bought a new car, my wife would be happy. Were I to buy a new car, my wife would be happy.

If I went to Russia, I would visit Moscow. Were I to go to Russia, I would visit Moscow.

Exercise 48:  In this exercise, the hypothetical situation is in the present, but we use the past tense verbs to show that they are not real.  Complete the following sentences, please.

If my father were alive today, ….. If my father were alive today, he would be very proud of his grandchildren.

If I had a new car, ….. If I had a new car, I would not use it as a truck as I now do with my old car.

1.  If I had a million dollars,

2.  If today were Saturday,

3.  If I had more free time in my life,

4.  If it snowed in June,

5.  If you spoke English as well as I do,

6.  If I found $1,000 on the street in a paper bag,

7.  If I were a professional athlete,

8.  If you still lived in your native country,

9.  If I could go anywhere I wanted to on vacation,

10.  If someone put a gun to my head and demanded all of my money,

11.  If you didn’t go to school,

12.  If you were younger,

Exercise 49:  Complete the following sentences, please.

1.  I would learn to play the guitar if

2.  If I had a lot of money,

3.  My friend would speak better English if

4.  If I wrote better,

5.  I would be happier in life if

6.  Some children would do much better in school if

7.  I would get in trouble if

8.  If the electricity went out right now

9.  People would be healthier if

10.  If America didn’t spend so much money on wars around the world,

11.  My life would be much better if

12.  If my sister didn’t smoke cigarettes,

13.  I would go to the doctor if

14.  I could buy anything I wanted to if

15.  If I were president of the United States,  

Exercise 50:  Change the following class two conditional sentences by using WERE to begin the condition, please.

If I saw a ghost, I would be very scared.   Were I to see a ghost, I would be very scared.

If my mother were alive, she would love to listen to my son’s music. Were my mother alive, she would love to listen to my son’s music.

1.  If you were my child, you would speak perfect English.

2.  If I were an airplane pilot, I would fly planes every day.

3.  If my wife were sitting here, she might learn more English grammar.

4.  If today were Sunday, you wouldn’t be in my class.

5.  If I were sick now, I wouldn’t be to class.

6.  If I had a lot of hair, I wouldn’t were a hat.

7.  If my son ate three hamburgers, his stomach would hurt him.

8.  If I lost $1,000 gambling, my wife would kill me.

9.  If I wore dirty shoes in the house, she would kill me again.

10.  If I got a DWI, my wife would kill me a third time.

11.  If I were to shave my beard, my students might not recognize me.

12.  If I had more space, I would write more sentences.

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  • Conditional Statement

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What Is A Conditional Statement?

In mathematics, we define statement as a declarative statement which may either be true or may be false. Often sentences that are mathematical in nature may not be a statement because we might not know what the variable represents. For example, 2x + 2 = 5. Now here we do not know what x represents thus if we substitute the value of x (let us consider that x = 3) i.e., 2 × 3 = 6. Therefore, it is a false statement. So, what is a conditional statement? In simple words, when through a statement we put a condition on something in return of something, we call it a conditional statement. For example, Mohan tells his friend that “if you do my homework, then I will pay you 50 dollars”. So what is happening here? Mohan is paying his friend 50 dollars but places a condition that if only he’s work will be completed by his friend. A conditional statement is made up of two parts. First, there is a hypothesis that is placed after “if” and before the comma and second is a conclusion that is placed after “then”. Here, the hypothesis will be “you do my homework” and the conclusion will be “I will pay you 50 dollars”. Now, this statement can either be true or may be false. We don’t know. 

A hypothesis is a part that is used after the 'if' and before the comma. This composes the first part of a conditional statement. For example, the statement, 'I help you get an A+ in math,' is a hypothesis because this phrase is coming in between the 'if' and the comma. So, now I hope you can spot the hypothesis in other examples of a conditional statement. Of course, you can. Here is a statement: 'If Miley gets a car, then Allie's dog will be trained,' the hypothesis here is, 'Miley gets a car.' For the statement, 'If Tom eats chocolate ice cream, then Luke eats double chocolate ice cream,' the hypothesis here is, 'Tom eats chocolate ice cream. Now it is time for you to try and locate the hypothesis for the statement, 'If the square is a rectangle, then the rectangle is a quadrilateral'?

A conclusion is a part that is used after “then”. This composes the second part of a conditional statement. For example, for the statement, “I help you get an A+ in math”, the conclusion will be “you will give me 50 dollars”. The next statement was “If Miley gets a car, then Allie's dog will be trained”, the conclusion here is Allie's dog will be trained. It is the same with the next statement and for every other conditional statement.   

How Do We Know If A Statement Is True or False? 

In mathematics, the best way we can know if a statement is true or false is by writing a mathematical proof. Before writing a proof, the mathematician must find if the statement is true or false that can be done with the help of exploration and then by finding the counterexample. Once the proof is discovered, the mathematician must communicate this discovery to those who speak the language of maths. 

Converse, Inverse, contrapositive, And Bi-conditional Statement

We usually use the term “converse” as a verb for talking and chatting and as a noun we use it to represent a brand of footwear. But in mathematics, we use it differently. Converse and inverse are the two terms that are a connected concept in the making of a conditional statement.

If we want to create the converse of a conditional statement, we just have to switch the hypothesis and the conclusion. To create the inverse of a conditional statement, we have to turn both the hypothesis and the conclusion to the negative. A contrapositive statement can be made if we first interchange the hypothesis and conclusion then make them both negative. In a bi-conditional statement, we use “if and only if” which means that the hypothesis is true only if the condition is true. For example, 

If you eat junk food, then you will gain weight is a conditional statement.

If you gained weight, then you ate junk food is a converse of a conditional statement.

If you do not eat junk food, then you will not gain weight is an inverse of a conditional statement.

If yesterday was not Monday, then today is not Tuesday is a contrapositive statement. 

Today is Tuesday if and only if yesterday was Monday is a bi-conventional statement.   

Image will be uploaded soon

A Conditional Statement Truth Table

In the table above, p→q will be false only if the hypothesis(p) will be true and the conclusion(q) will be false, or else p→q will be true. 

Conditional Statement Examples

Below, you can see some of the conditional statement examples.

Example 1) Given, P = I do my work; Q = I get the allowance

What does p→q represent?

Solution 1) In the sentence above, the hypothesis is “I do my work” and the conclusion is “ I get the allowance”. Therefore, the condition p→q represents the conditional statement, “If I do my work, then I get the allowance”. 

Example 2) Given, a = The sun is a ball of gas; b = 5 is a prime number. Write a→b in a sentence. 

Solution 2) The conditional statement a→b here is “if the sun is a ball of gas, then 5 is a prime number”.

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FAQs on Conditional Statement

1. How many types of conditional statements are there?

There are basically 5 types of conditional statements.

If statement, if-else statement, nested if-else statement, if-else-if ladder, and switch statement are the basic types of conditional statements. If a function displays a statement or performs a function on the condition if the statement is true. If-else statement executes a block of code if the condition is true but if the condition is false, a new block of code is placed. The switch statement is a selection control mechanism that allows the value of a variable to change the control flow of a program. 

2. How are a conditional statement and a loop different from each other?

A conditional statement is sometimes used by a loop but a loop is of no use to a conditional statement. A conditional statement is basically a “yes” or a “no” i.e., if yes, then take the first path else take the second one. A loop is more like a cyclic chain starting from the start point i.e., if yes, then take path a, if no, take path b and it comes back to the start point. 

Conditional statement executes a statement based on a condition without causing any repetition. 

A loop executes a statement repeatedly. There are two loop variables i.e., for loop and while loop.

Calcworkshop

Conditional Statement If Then's Defined in Geometry - 15+ Examples!

// Last Updated: January 21, 2020 - Watch Video //

In today’s geometry lesson , you’re going to learn all about conditional statements!

Jenn (B.S., M.Ed.) of Calcworkshop® introducing conditional statements

Jenn, Founder Calcworkshop ® , 15+ Years Experience (Licensed & Certified Teacher)

We’re going to walk through several examples to ensure you know what you’re doing.

In addition, this lesson will prepare you for deductive reasoning and two column proofs later on.

Here we go!

What are Conditional Statements?

To better understand deductive reasoning, we must first learn about conditional statements.

A conditional statement has two parts: hypothesis ( if ) and conclusion ( then ).

In fact, conditional statements are nothing more than “If-Then” statements!

Sometimes a picture helps form our hypothesis or conclusion. Therefore, we sometimes use Venn Diagrams to visually represent our findings and aid us in creating conditional statements.

But to verify statements are correct, we take a deeper look at our if-then statements. This is why we form the converse , inverse , and contrapositive of our conditional statements.

What is the Converse of a Statement?

Well, the converse is when we switch or interchange our hypothesis and conclusion.

Conditional Statement : “If today is Wednesday, then yesterday was Tuesday.”

Hypothesis : “If today is Wednesday” so our conclusion must follow “Then yesterday was Tuesday.”

So the converse is found by rearranging the hypothesis and conclusion, as Math Planet accurately states.

Converse : “If yesterday was Tuesday, then today is Wednesday.”

What is the Inverse of a Statement?

Now the inverse of an If-Then statement is found by negating (making negative) both the hypothesis and conclusion of the conditional statement.

So using our current conditional statement, “If today is Wednesday, then yesterday was Tuesday”.

Inverse : “If today is not Wednesday, then yesterday was not Tuesday.”

What is a Contrapositive?

And the contrapositive is formed by interchanging the hypothesis and conclusion and then negating both.

Contrapositive : “If yesterday was not Tuesday, then today is not Wednesday”

What is a Biconditional Statement?

A statement written in “if and only if” form combines a reversible statement and its true converse. In other words the conditional statement and converse are both true.

Continuing with our initial condition, “If today is Wednesday, then yesterday was Tuesday.”

Biconditional : “Today is Wednesday if and only if yesterday was Tuesday.”

examples of conditional statements

Examples of Conditional Statements

In the video below we will look at several harder examples of how to form a proper statement, converse, inverse, and contrapositive. And here’s a big hint…

Whenever you see “con” that means you switch! It’s like being a con-artist!

Moreover, we will detail the process for coming up with reasons for our conclusions using known postulates. We will review the ten postulates that we have learned so far, and add a few more problems dealing with perpendicular lines, planes, and perpendicular bisectors.

After this lesson, we will be ready to tackle deductive reasoning head-on, and feel confident as we march onward toward learning two-column proofs!

Conditional Statements – Lesson & Examples (Video)

  • Introduction to conditional statements
  • 00:00:25 – What are conditional statements, converses, and biconditional statements? (Examples #1-2)
  • 00:05:21 – Understanding venn diagrams (Examples #3-4)
  • 00:11:07 – Supply the missing venn diagram and conditional statement for each question (Examples #5-8)
  • Exclusive Content for Member’s Only
  • 00:17:48 – Write the statement and converse then determine if they are reversible (Examples #9-12)
  • 00:29:17 – Understanding the inverse, contrapositive, and symbol notation
  • 00:35:33 – Write the statement, converse, inverse, contrapositive, and biconditional statements for each question (Examples #13-14)
  • 00:45:40 – Using geometry postulates to verify statements (Example #15)
  • 00:53:23 – What are perpendicular lines, perpendicular planes and the perpendicular bisector?
  • 00:56:26 – Using the figure, determine if the statement is true or false (Example #16)
  • Practice Problems with Step-by-Step Solutions
  • Chapter Tests with Video Solutions

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How to Understand ‘If-Then’ Conditional Statements: A Comprehensive Guide

In math, and even in everyday life, we often say 'if this, then that.' This is the essence of conditional statements. They set up a condition and then describe what happens if that condition is met. For instance, 'If it rains, then the ground gets wet.' These statements are foundational in math, helping us build logical arguments and solve problems. In this guide, we'll dive into the clear-cut world of conditional statements, breaking them down in both simple terms and their mathematical significance.

How to Understand ‘If-Then’ Conditional Statements: A Comprehensive Guide

Step-by-step Guide: Conditional Statements

Defining Conditional Statements: A conditional statement is a logical statement that has two parts: a hypothesis (the ‘if’ part) and a conclusion (the ‘then’ part). Written symbolically, it takes the form: \( \text{If } p, \text{ then } q \) Where \( p \) is the hypothesis and \( q \) is the conclusion.

Truth Values: A conditional statement is either true or false. The only time a conditional statement is false is when the hypothesis is true, but the conclusion is false.

Converse, Inverse, and Contrapositive: 1. Converse: The converse of a conditional statement switches the hypothesis and the conclusion. For the statement “If \( p \), then \( q \)”, the converse is “If \( q \), then \( p \)”.

2. Inverse: The inverse of a conditional statement negates both the hypothesis and the conclusion. For the statement “If \( p \), then \( q \)”, the inverse is “If not \( p \), then not \( q \)”.

3. Contrapositive: The contrapositive of a conditional statement switches and negates both the hypothesis and the conclusion. For the statement “If \( p \), then \( q \)”, the contrapositive is “If not \( q \), then not \( p \)”.

Example 1: Simple Conditional Statement: “If it is raining, then the ground is wet.”

Solution: Hypothesis \(( p )\): It is raining. Conclusion \(( q )\): The ground is wet.

Example 2: Determining Truth Value Statement: “If a shape has four sides, then it is a rectangle.”

Solution: This statement is false because a shape with four sides could be a square, trapezoid, or other quadrilateral, not necessarily a rectangle.

Example 3: Converse, Inverse, and Contrapositive Statement: “If a number is even, then it is divisible by \(2\).”

Solution: Converse: If a number is divisible by \(2\), then it is even. Inverse: If a number is not even, then it is not divisible by \(2\). Contrapositive: If a number is not divisible by \(2\), then it is not even.

Practice Questions:

  • Write the converse, inverse, and contrapositive for the statement: “If a bird is a penguin, then it cannot fly.”
  • Determine the truth value of the statement: “If a shape has three sides, then it is a triangle.”
  • For the statement “If an animal is a cat, then it is a mammal,” which of the following is its converse? a) If an animal is a mammal, then it is a cat. b) If an animal is not a cat, then it is not a mammal. c) If an animal is not a mammal, then it is not a cat.
  • Converse: If a bird cannot fly, then it is a penguin. Inverse: If a bird is not a penguin, then it can fly. Contrapositive: If a bird can fly, then it is not a penguin.
  • The statement is true. A shape with three sides is defined as a triangle.
  • a) If an animal is a mammal, then it is a cat.

by: Effortless Math Team about 6 months ago (category: Articles )

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Telling the whole truth: conditional truth tables

curious

One day - in the not so far off future - when you’re an amazing lawyer (having first crushed the LSAT, of course), any witnesses you call to testify will have to swear to tell the truth, the whole truth, and nothing but the truth. Unfortunately, some truths are harder to determine than others. While we may be able to tell the truth about our own life experiences, things get a little trickier when it comes to the ‘truth’ of conditional statements.

In our first blog post on conditionals , we covered what conditional statements are, as well as going through the differences between necessary and sufficient conditions. The second post discussed manipulating conditional statements , so that you could find the inverse, converse, and contrapositive of a conditional (with a little help from Missy Elliott). In this post, we’ll be going over how a table setup can help you figure out the truth of conditional statements.

As a refresher, conditional statements are made up of two parts, a hypothesis (represented by p) and a conclusion (represented by q). In a truth table, we will lay out all possible combinations of truth values for our hypothesis and conclusion and use those to figure out the overall truth of the conditional statement.

Conditional statement truth table

It will take us four combination sets to lay out all possible truth values with our two variables of p and q, as shown in the table below. In the first set, both p and q are true. If both a hypothesis and a conclusion are true, it makes sense that the statement as a whole is also true. Take the conditional ‘If Claire buys a dog, I’ll help her take care of it’. If it’s true that Claire buys a dog and it’s true that I follow through on my promise to help her care for it (true hypothesis/true conclusion), then the conditional as a whole is true. However, if it’s true that Claire buys a dog but I decide to break my promise and not help her care for it (true hypothesis/false conclusion), then the conditional statement is proven false because the condition p that is supposed to imply the conclusion q did not actually do so.

It may seem to get trickier when you have a false hypothesis/true conclusion or false hypothesis/false conclusion, but there’s a rule that can help you out here: whenever the hypothesis or ‘p’ of a conditional is false, the conditional as a whole is always true. That’s because if the condition is never carried out, it doesn’t matter what the conclusion is - if Claire never gets a dog, I can never break my promise to help her take care of it. So, if your hypothesis is false, your conditional is always true. And the only way for your conditional to be false is if the hypothesis is true but its conclusion is false. Here you can look at a conditional truth table and compare it to another example statement given below:

Screen Shot 2018-05-14 at 10.08.51 PM

Let’s go through another example statement. Take the conditional ‘If Ivy does well on her test, she will pass the class’.  

True p/true q: Ivy does well on her test, Ivy passes the class. The condition is met and the conclusion is met, so the conditional is true.  

True p/false q: Ivy does well on her test, Ivy does not pass the class. The condition is met but the conclusion that is supposed to result from that condition does not occur, so the conditional is false.

False p/true q: Ivy doesn’t do well on her test, Ivy passes the class. You should know immediately that the conditional is true because the hypothesis or ‘p’ is false.

False p/false q: Ivy doesn’t do well on her test, Ivy does not pass the class. You should know immediately that the conditional is true because the hypothesis or ‘p’ is false.

  Warning: Keep in mind that whether or not something seems true or is true in the real world doesn’t matter here. What matters is the logical outcome that you are able to find by using the truth table.

Y ou can now put all three blog posts on conditionals into practice at once. Now that we’ve gone over truth tables for conditionals, try your hand at writing them out for the inverse, converse, and contrapositive. It may take a little bit to think through what the answers should be, but it will help you bring together all your knowledge on conditionals and their manipulations. The completed tables are below so you can check your work. Once you’ve written out these tables, attempt to work through them using real examples of conditional statements as we did above. The LSAT may not have much overlap with carpentry, but when it comes to building tables practice always makes perfect.

Screen Shot 2018-05-14 at 10.10.31 PM

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Conditional Statements

Two common types of statements found in the study of logic are conditional and biconditional statements. They are formed by combining two statements which we then we call compound statements. What if we were to say, "If it snows, then we don't go outside." This is two statements combined. They are often called if-then statements. As in, "IF it snows, THEN we don't go outside." They are a fundamental building block of computer programming.

Writing conditional statements

A statement written in if-then format is a conditional statement.

It looks like

This represents the conditional statement:

"If p then q ."

A conditional statement is also called an implication.

If a closed shape has three sides, then it is a triangle.

The part of the statement that follows the "if" is called the hypothesis. The part of the statement that follows the "then" is the conclusion.

So in the above statement,

If a closed shape has three sides, (this is the hypothesis)

Then it is a triangle. (this is the conclusion)

Identify the hypothesis and conclusion of the following conditional statement.

A polygon is a hexagon if it has six sides.

Hypothesis: The polygon has six sides.

Conclusion: It is a hexagon.

The hypothesis does not always come first in a conditional statement. You must read it carefully to determine which part of the statement is the hypothesis and which part is the conclusion.

Truth table for conditional statement

The truth table for any two given inputs, say A and B , is given by:

  • If A and B are both true, then A → B is true.
  • If A is true and B is false, then A → B is false.
  • If A is false and B is true, then A → B is true.
  • If A and B are both false, then A → B is true.

Take our conditional statement that if it snows, we do not go outside.

If it is snowing ( A is true) and we do go outside ( B is false), then the statement A → B is false.

If it is not snowing ( A is false), it doesn't matter if we go outside or not ( B is true or false), because A → B is impossible to determine if A is false, so the statement A → B can still be true.

Biconditional statements

A biconditional statement is a combination of a statement and its opposite written in the format of "if and only if."

For example, "Two line segments are congruent if and only if they are the same length."

This is a combination of two conditional statements.

"Two line segments are congruent if they are the same length."

"Two line segments are the same length if they are congruent."

A biconditional statement is true if and only if both the conditional statements are true.

Biconditional statements are represented by the symbol:

p ↔ q

p ↔ q = p → q ∧ q → p

Writing biconditional statements

Write the two conditional statements that make up this biconditional statement:

I am punctual if and only if I am on time to school every day.

The two conditional statements that have to be true to make this statement true are:

  • I am punctual if I am on time to school every day.
  • I am on time to school every day if I am punctual.

A rectangle is a square if and only if the adjacent sides are congruent.

  • If the adjacent sides of a rectangle are congruent then it is a square.
  • If a rectangle is a square then the adjacent sides are congruent.

Topics related to the Conditional Statements

Conjunction

Counter Example

Biconditional Statement

Flashcards covering the Conditional Statements

Symbolic Logic Flashcards

Introduction to Proofs Flashcards

Practice tests covering the Conditional Statements

Introduction to Proofs Practice Tests

Get help learning about conditional statements

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IMAGES

  1. PPT

    example of conditional hypothesis

  2. Conditional Statements in Geometry

    example of conditional hypothesis

  3. For September 9th class 8. CONDITIONAL STATEMENTS

    example of conditional hypothesis

  4. How to Write a Hypothesis: The Ultimate Guide with Examples

    example of conditional hypothesis

  5. PPT

    example of conditional hypothesis

  6. Conditional Statements

    example of conditional hypothesis

VIDEO

  1. Conditional Sentences

  2. Conditional Statements Hypothesis and conclusion

  3. conditional probability

  4. Binomial distribution and Conditional Probability- (Project Maths HL Example)

  5. 27 Consistent Hypothesis and Inconsistent Hypothesis Example

  6. Conditional Probability Explained with Examples, Probability & Statistics

COMMENTS

  1. Conditional Statement: Definition, Truth Table, Examples

    The hypothesis or condition will begin with the "if" part, and the conclusion or action will begin with the "then" part. A conditional statement is also called "implication.". Conditional Statements Examples: Example 1: If it is Sunday, then you can go to play. Hypothesis: If it is Sunday.

  2. 1.1: Statements and Conditional Statements

    Record the results for at least five different examples where the hypothesis of this conditional statement is true. 2. "If \(n\) is a positive integer, then \(n^2 - n +41\) is a prime number." (Remember that a prime number is a positive integer greater than 1 whose only positive factors are 1 and itself.)

  3. 5.3.1: Conditional/Hypothetical Sentences

    A past hypothetical situation (imaginary, did not happen, or is contrary to fact) influences a present or future hypothetical situation. This is actually a combination of a Class Three Conditional and a Class Two Conditional. Form: If + past perfect tense, would or could + verb stem. Examples:

  4. Understanding a Conditional Statement

    In Example 2, "The sun is made of gas" is the hypothesis and "3 is a prime number" is the conclusion. Note that the logical meaning of this conditional statement is not the same as its intuitive meaning. In logic, the conditional is defined to be true unless a true hypothesis leads to a false conclusion.

  5. 3.3: Truth Tables- Conditional, Biconditional

    A biconditional is a logical conditional statement in which the hypothesis and conclusion are interchangeable. A biconditional is written as p ↔ q p ↔ q and is translated as " p p if and only if q′′ q ′ ′. Because a biconditional statement p ↔ q p ↔ q is equivalent to (p → q) ∧ (q → p), ( p → q) ∧ ( q → p), we may ...

  6. Conditional Sentences

    A subordinate clause with a verb in the past subjunctive form (e.g., "looked") A main clause using a modal verb (usually "would," "could," or "might") along with the infinitive form of the main verb (e.g., "sing") Examples: Second conditional sentences. If I were rich, then I would drive a different car every day.

  7. PDF Section 1.2: Conditional Statements

    with an example so we can understand when a conditional statement should be true. For the example, we need the following notation and terminolgy: Notation 1.1. If p and q are statements, the conditional of q by p is "if pthen q" denoted p → q. We call pthe hypothesis of the conditional and q the conclusion. Example 1.2.

  8. Conditional Statement

    Conditional Statement. A conditional statement is a part of mathematical reasoning which is a critical skill that enables students to analyze a given hypothesis without any reference to a particular context or meaning. In layman words, when a scientific inquiry or statement is examined, the reasoning is not based on an individual's opinion.

  9. 2.4 Truth Tables for the Conditional and Biconditional

    Use and Apply the Conditional to Construct a Truth Table. A conditional is a logical statement of the form if p p, then q q.The conditional statement in logic is a promise or contract. The only time the conditional, p → q, p → q, is false is when the contract or promise is broken. For example, consider the following scenario.

  10. Determining the Truth of Conditional Statements

    Step 1: Identify the hypothesis and conclusion of the conditional statement. Any of these statements above can be considered to be a hypothesis p or a conclusion q. It all depends on how we ...

  11. 2.11: If Then Statements

    The conclusion is the result of a hypothesis. Figure 2.11.1 2.11. 1. If-then statements might not always be written in the "if-then" form. Here are some examples of conditional statements: Statement 1: If you work overtime, then you'll be paid time-and-a-half. Statement 2: I'll wash the car if the weather is nice.

  12. 4.8: Conditional/Hypothetical Clauses

    Conditional / Hypothetical Sentences. ... and an independent clause which is a result of the condition or hypothesis. A conditional sentence is one that is real or possibly can happen; a hypothetical sentence is one that is only imaginary - it either will not happen or did not happen. ... Examples: If my sister visits Seattle, I will take her ...

  13. Conditional Statement

    A hypothesis is a part that is used after the 'if' and before the comma. This composes the first part of a conditional statement. For example, the statement, 'I help you get an A+ in math,' is a hypothesis because this phrase is coming in between the 'if' and the comma.

  14. PDF 2-1 Conditional Statements

    form,the letter p stands for the hypothesis and the letter q stands for the conclusion. Quick Check 77 7 EXAMPLE Real-World Connection Quick Check 66 6 EXAMPLE Key Concepts Summary Conditional Statements and Converses Statement Example Symbolic Form You Read It Conditional If an angle is a straight angle, p S q If p, then q. then its measure is ...

  15. Conditional Statements (15+ Examples in Geometry)

    Example. Conditional Statement: "If today is Wednesday, then yesterday was Tuesday.". Hypothesis: "If today is Wednesday" so our conclusion must follow "Then yesterday was Tuesday.". So the converse is found by rearranging the hypothesis and conclusion, as Math Planet accurately states. Converse: "If yesterday was Tuesday, then ...

  16. How to Understand 'If-Then' Conditional ...

    A conditional statement is a logical statement that has two parts: a hypothesis (the 'if' part) and a conclusion (the 'then' part). Written symbolically, it takes the form: \( \text{If } p, \text{ then } q \) Where \( p \) is the hypothesis and \( q \) is the conclusion. Truth Values: A conditional statement is either true or false.

  17. CC

    Conditional statement truth table. It will take us four combination sets to lay out all possible truth values with our two variables of p and q, as shown in the table below. In the first set, both p and q are true. If both a hypothesis and a conclusion are true, it makes sense that the statement as a whole is also true.

  18. Conditional Statements

    The hypothesis does not always come first in a conditional statement. You must read it carefully to determine which part of the statement is the hypothesis and which part is the conclusion. ... Example 4. Write the two conditional statements that make up this biconditional statement: A rectangle is a square if and only if the adjacent sides are ...

  19. PDF Conditional Probability, Hypothesis Testing, and the Monty Hall Problem

    1 Hypothesis Testing If someone tells you that a test for cancer (or alchohol, or drugs, or lies etc.) is "98 percent accurate", it would be wise to ask them what they mean, as the following example will demonstrate: Suppose that a person goes in for a routine medical test, and one of the tests says that he has cancer.

  20. Conditional Statements and Their Converse (Examples & Video)

    Conditional statements start with a hypothesis and end with a conclusion. Conditional statement examples. If my cat is hungry, then she will rub my leg. If a polygon has exactly four sides, then it is a quadrilateral. If triangles are congruent, then they have equal corresponding angles. Conditional Statement Examples

  21. If-Then Statements ( Read )

    The hypothesis is the first, or "if," part of a conditional statement. The conclusion is the second, or "then," part of a conditional statement. The conclusion is the result of a hypothesis. Keep in mind that conditional statements might not always be written in the "if-then" form. Here are a few examples.

  22. How to Write a Strong Hypothesis

    5. Phrase your hypothesis in three ways. To identify the variables, you can write a simple prediction in if…then form. The first part of the sentence states the independent variable and the second part states the dependent variable. If a first-year student starts attending more lectures, then their exam scores will improve.

  23. Biconditional Statement

    A biconditional statement combines a conditional statement with its converse statement. Both the conditional and converse statements must be true to produce a biconditional statement. If we remove the if-then part of a true conditional statement, combine the hypothesis and conclusion, and tuck in a phrase "if and only if," we can create ...