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## Manhattan 700-800 level

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bryan88 Really wants to Beat The GMAT!
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Manhattan 700-800 level Sun May 13, 2012 8:13 am
Elapsed Time: 00:00
• Lap #[LAPCOUNT] ([LAPTIME])
If there are x men and y women in a choir, and there are z more men than there are women in that choir, what is z?

(1) x² - 2xy + y² - 9 = 0

(2) x² + 2xy + y² - 225 = 0

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aneesh.kg GMAT Destroyer!
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Sun May 13, 2012 8:40 am
Given:
x = y + z
z = (x - y)
What is the value of z?
Since none of the statements contain 'z', we will look for finding the value (x - y).

Statement(1):
(x - y)^2 = 9
(x - y) = 3 or -3
-3 is ruled out. (because it is given that there are more men than women, so x > y)
(x - y) = 3 = z
SUFFICIENT

Statement(2):
(x + y)^2 = 225
(x + y) = 15 or -15
In any case, we're not getting (x - y) from this.
INSUFFICIENT

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Aneesh Bangia
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aneesh.bangia@gmail.com

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