GMAT Prep help

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GMAT Prep help

by akshatgupta87 » Wed Apr 27, 2011 6:29 am
Is there any shorter way of doing this question beside plugging in the values?

Q.) If x is not equal to -y, is (x-y)/(x+y) > 1 ?
1) x>0
2) y<0

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by GMATGuruNY » Wed Apr 27, 2011 7:14 am
akshatgupta87 wrote:Is there any shorter way of doing this question beside plugging in the values?

Q.) If x is not equal to -y, is (x-y)/(x+y) > 1 ?
1) x>0
2) y<0
Plugging in values is extremely efficient if you try combinations that satisfy both statements.

Let x=2 and y=-1.
Is (2-(-1)) / (2+(-1)) > 1? Yes.
Let x=1 and y=-2.
Is (1-(-2)) / (1+(-2)) > 1? No.

Since the combinations above satisfy both statements, and in the first case the answer is Yes and in the second case the answer is No, the correct answer is E.
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by Chaitanya_1986 » Wed Apr 27, 2011 8:05 am
Hi Mitch,

Can we do like this

x-y/x+y>1

= x-y>x+y
= -2y>0
= y < 0

this nothing but option B) so B is correct

so answer is B)

is this wrong way of approach????

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by akshatgupta87 » Wed Apr 27, 2011 2:50 pm
ya..even i had the same doubt..