Question

Which of the following is the inverse of the proposition "If a number is prime, then it is odd"?

• A. If a number is not prime, then it is odd.
• B. If a number is not a prime, then it is not odd.
• C. If a number is not odd, then it is not a prime.
• D. If a number is not odd, then it is a prime.

Answer 1

Answer: (B)

If a number is not a prime, then it is not odd.

p : A number is prime
q : It is odd
We have $p\to q$
The inverse of $p\to q$ is $\sim p\to \sim q$
i.e. If a number is not a prime then it is not odd.