State the converse and contrapositive of each of the following statements:

(i) p: A positive integer is prime only if it has no divisors other than 1 and itself.


(ii) q: I go to a beach whenever it is a sunny day.


(iii) r: If it is hot outside, then you feel thirsty.

We know that


the converse of a given statement “if p, then q” is if q, then p and the contra positive of the statement if p, then q is “if q, then p”.


(i) The statement p can be rewritten as


If a positive integer is prime, then it has n divisors other than 1 and the number itself.


Converse of statement p is


If a positive integer has no divisors other than 1 and the number itself, then it is prime.


Contra positive of statement p is


If a positive integer has divisors other than 1 and the number itself, then it is not prime.


(ii) The statement q can be rewritten as


If it is a sunny day, then I go to a beach.


Converse of statement q is


If I go to a beach, then it is a sunny day.


Contra positive of statement q is


If don’t go to a beach, it is not a sunny day.


(iii) Converse of statement r is


If you feel thirsty, then it is hot outside.


Contra positive of statement r is


If you don’t feel thirsty, then it is not hot outside.


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