If z is an integer, is z even?
(1) z/2 is even.
(2) 3z is even.
OA D
Source: Manhattan Prep
If z is an integer, is z even?
This topic has expert replies
-
BTGmoderatorDC
- Moderator
- Posts: 6520
- Joined: 07 Sep 2017
- Followed by:20 members
GMAT/MBA Expert
-
[email protected]
- GMAT Instructor
- Posts: 16068
- Joined: 08 Dec 2008
- Location: Vancouver, BC
- Thanked: 5254 times
- Followed by:1268 members
- GMAT Score:770
Timer
00:00
Your Answer
A
B
C
D
E
Global Stats
Target question: Is z an even integer?BTGmoderatorDC wrote: ↑Tue Jan 25, 2022 5:42 pmIf z is an integer, is z even?
(1) z/2 is even.
(2) 3z is even.
OA D
Source: Manhattan Prep
Aside: Integer n is even if we can express n as n = 2k for some integer k
Statement 1: z/2 is an even integer.
This means z/2 =2k for some integer k
Multiply both sides by 2 to get: z = 4k
This tells us that z is a multiple of 4, which means z is definitely even
Since we can answer the target question with certainty, statement 1 is SUFFICIENT
Statement 2: 3z is even .
Since 3 is ODD, the only way that 3z can be even is if z is EVEN.
Since we can answer the target question with certainty, statement 2 is SUFFICIENT
Answer: D
