GMATprep DS question

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GMATprep DS question

by mlane25269 » Mon Jun 30, 2008 6:01 pm
Hi guys!! How do I solve? Thanks!
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by atlantic » Tue Jul 01, 2008 1:53 am
Answer is C.

There is only one way to satisfy both statements (1) and (2), and that is when both x and y are positive.

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by mlane25269 » Tue Jul 01, 2008 8:15 am
ok I guess I'm not following this because based on stmt 2 it says that x/y = 1 can equal either both negative or both positive to be greater than 1 but how would that substitute back into stmt 1?

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by ildude02 » Tue Jul 01, 2008 2:46 pm
It took me a while to combine both of the statemets, but I hope there is easy way about solving this problem. Any thoughts?

From 1) x= y + 1/2 ;=> x > y; so it can be anything. NOT SUFF
from 2) we can dervie that x and y must be positive and also x > y to satisfy the equation. Similarly, x and y can be both be negative and x< y. NOT SUFF:

combining both, I see that x > y common to both and from 2 , we also know that when x > y, x and y must be positive to satisy equation 2.