Question

Rewrite the following statement with "if-then ”in five different ways conveying the same meaning. If a natural number is odd then its square is also odd.

Answer 1

(i) A natural number is odd implies that its square is odd.

(ii) A natural number is odd only if its square is odd.

(iii) For a natural number to be odd it is necessary that its square is odd.

(iv) For the square of a natural number to be odd it is sufficient that the number is odd.

(v) If the square of a natural number is not odd then the natural number is not odd.