X as integer

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Source: — Data Sufficiency |

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by mike22629 » Wed May 13, 2009 8:22 am
IMO A.

You are looking for the signs of x and y. For x/y to be negative exactly one of them has to be positive and the other negative.

1.) tells you one is neg and one is positive so sufficient.
2.) tells you nothing about the signs. Ins.

A

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by criszerriny » Wed May 13, 2009 8:32 am
Answer is D. X^2 and Y^2 will always be positive regardless of the signs, so X/Y>0 at all times.

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Re: X as integer

by Vemuri » Wed May 13, 2009 8:41 am
IMO A.

If x/y<0, it means that either x or y is negative.

1 --> Suff, either x or y is negative to make the fraction less than 0.

2 --> Insuff. (x^2/y^2)>1. We can't comment on x/y because whatever their signs, the square will make it greater than 0.

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by criszerriny » Wed May 13, 2009 9:28 am
for some reason, I read this problem wrong.. A is correct.