If w, x and y are different positive integers, and wxy = 24, is xy divisible by 6?
(1) wy is not divisible by 6.
(2) x is even.
The OA is E.
How can I conclude that the correct option is E? Experts, could you help me?
5-Day Free Trial
5-day free, full-access trial TTP
Available with Beat the GMAT members only code
MORE DETAILS
If w, x and y are different positive integers
This topic has expert replies
GMAT/MBA Expert
-
[email protected]
- Elite Legendary Member
- Posts: 10392
- Joined: Sun Jun 23, 2013 6:38 pm
- Location: Palo Alto, CA
- Thanked: 2867 times
- Followed by:511 members
- GMAT Score:800
Hi Vincen,
Certain Quant questions include 'restrictions' that limit the number of possible outcomes. In those situations, it can often be useful to list out all of the possibilities BEFORE you actually approach the rest of the prompt.
Here, we're told that W, X and Y are DIFFERENT positive integers and that (W)(X)(Y) = 24. Based on this information, these are the only possibilities:
1, 2 and 12
1, 3 and 8
1, 4 and 6
2, 2, and 6
2, 3 and 4
We're asked if (X)(Y) is divisible by 6. This is a YES/NO question.
1) (W)(Y) is NOT divisible by 6...
IF... W=1, Y=4, X=6 then the answer to the question is YES.
IF... W=3, Y=1, X=8 then the answer to the question is NO.
Fact 1 is INSUFFICIENT
2) X is EVEN.
We can use the same 'TESTs' from Fact 1 in Fact 2....
IF... W=1, Y=4, X=6 then the answer to the question is YES.
IF... W=3, Y=1, X=8 then the answer to the question is NO.
Fact 2 is INSUFFICIENT
Combined, we already have to different examples that 'fit' BOTH Facts and provide two different results (a "YES" and a "NO"), so there's no more work needed.
Combined, INSUFFICIENT
Final Answer: E
GMAT assassins aren't born, they're made,
Rich
Certain Quant questions include 'restrictions' that limit the number of possible outcomes. In those situations, it can often be useful to list out all of the possibilities BEFORE you actually approach the rest of the prompt.
Here, we're told that W, X and Y are DIFFERENT positive integers and that (W)(X)(Y) = 24. Based on this information, these are the only possibilities:
1, 2 and 12
1, 3 and 8
1, 4 and 6
2, 2, and 6
2, 3 and 4
We're asked if (X)(Y) is divisible by 6. This is a YES/NO question.
1) (W)(Y) is NOT divisible by 6...
IF... W=1, Y=4, X=6 then the answer to the question is YES.
IF... W=3, Y=1, X=8 then the answer to the question is NO.
Fact 1 is INSUFFICIENT
2) X is EVEN.
We can use the same 'TESTs' from Fact 1 in Fact 2....
IF... W=1, Y=4, X=6 then the answer to the question is YES.
IF... W=3, Y=1, X=8 then the answer to the question is NO.
Fact 2 is INSUFFICIENT
Combined, we already have to different examples that 'fit' BOTH Facts and provide two different results (a "YES" and a "NO"), so there's no more work needed.
Combined, INSUFFICIENT
Final Answer: E
GMAT assassins aren't born, they're made,
Rich
