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x not equal to -y

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by GMATGuruNY » Tue Dec 06, 2011 10:28 am
jainrahul1985 wrote:x not equal to -y

Is x-y/x+y > 1?

1) x > 0
2) y < 0

OA E
Look for combinations that satisfy both statements.

Let x=1 and y=-2.
(x-y)/(x+y) = (1-(-2)) / (1+(-2)) = -3.

Let x=2 and y=-1.
(x-y)/(x+y) = (2-(-1)) / (2+(-1)) = 3.

Since in the first case (x-y)/(x+y) < 1, and in the second case (x-y)/(x+y) > 1, the two statements combined are INSUFFICIENT.

The correct answer is E.
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by Anurag@Gurome » Tue Dec 06, 2011 10:53 pm
jainrahul1985 wrote:x not equal to -y

Is x-y/x+y > 1?

1) x > 0
2) y < 0

OA E
Got a PM to reply on this thread.


Consider the following two cases,

1. x = 2 and y = -1 --> (x - y)/(x + y) = 3/1 = 3 > 1
2. x = 2 and y = -3 --> (x - y)/(x + y) = 5/(-1) = -5 < 1

Both of the above cases satisfy both the statements but in one case the answer is to the main question is YES in other case it is NO. Hence, both statements together is not sufficient to answer the question.

The correct answer is E.

Note: The problem can be solved algebraically too, but in that case the solution will be a bit more time consuming.
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