If \(r\) and \(s\) are integers, is \(r^2+s\) even?

This topic has expert replies
Legendary Member
Posts: 1622
Joined: Thu Mar 01, 2018 7:22 am
Followed by:2 members

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

If \(r\) and \(s\) are integers, is \(r^2+s\) even?

(1) The product of \(rs\) is odd.
(2) \(r\) is odd.

Answer: A

Source: GMAT Paper Tests

Junior | Next Rank: 30 Posts
Posts: 24
Joined: Wed Jun 29, 2011 1:47 am

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

The product rs can be odd only when both r and s are odd.
In such a case, \(r^2\) + s would be even, as the sq. of an odd number added to an odd number would be an even number
Thus A is sufficient
2nd option only mentions r is odd and nothing about s. Not sufficient.

Correct answer is thus A.