BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

If x is an integer, is x odd?

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Source: — Data Sufficiency |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16207
Joined: Mon Dec 08, 2008 6:26 pm
Location: Vancouver, BC
Thanked: 5254 times
Followed by:1268 members
GMAT Score:770

by Brent@GMATPrepNow » Wed Oct 18, 2017 1:09 pm
LUANDATO wrote:If x is an integer, is x odd?

(1) x + 4 is an odd integer.
(2) x/3 is NOT an even integer.
Target question: Is x odd?

Some important rules:
1. ODD + ODD = EVEN
2. ODD + EVEN = ODD
3. EVEN + EVEN = EVEN


Statement 1: x + 4 is an odd integer.
Since 4 is EVEN, we have: x + EVEN = ODD
From rule #2 above, we can see that x must be odd
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: x/3 is NOT an even integer.
There are several values of x that satisfy statement 2. Here are two:
Case a: x = 3. Here, x/3 = 3/3 = 1, and 1 is NOT an even integer. In this case, x IS odd
Case b: x = 4. Here, x/3 = 4/3 = 1.333333...., and 1.333333.... is NOT an even integer. In this case, x is NOT odd
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Answer: A

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
Post new topic Post Reply
• Page 1 of 1