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.
Solution by author:
Author just came up with "good" examples (counter cases) in BOTH cases. Good because both ARE SAME. How I indistinctly come up with them? [/img]
If w, x and y are different positive integers, and wxy =...
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- towerSpider
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- towerSpider
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And I think it is "good" also because the author came up with way too fast. Any input? Thanks.
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- GMATGuruNY
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List combinations of 3 distinct positive integers with a product of 24:towerSpider wrote: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.
1*2*12.
1*3*8
1*4*6
2*3*4.
Statement 1: wy is not divisible by 6
Case 1: w=1 and y=2, implying that x=12.
In this case, xy = 24, which is divisible by 6.
Case 2: w=1 and y=3, implying that x=8.
In this case, xy=24, which is divisible by 6.
But if w and y swap values in Case 2, xy will NOT be divisible by 6.
Case 3: w=3 and y=1, implying that x=8.
In this case, xy=8, which is NOT divisible by 6.
INSUFFICIENT.
Cases 1 and 3 also satisfy Statement 2.
Thus, even when both statements are satisfied, it's possible that xy is divisible by 6 or that xy is not divisible by 6.
The correct answer is E.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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