If x and y are positive, what is the value of x ?

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If x and y are positive, what is the value of x ?

(1) 200 percent of x equals 400 percent of y.
(2) xy is the square of a positive integer.

Here we are able to find a co-relation between x and y. What should be the answer here ?
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by netigen » Sat Jun 14, 2008 11:24 pm
Ans should be E

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by airan » Sun Jun 15, 2008 3:24 am
can u pls explain also ..
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by durgesh79 » Sun Jun 15, 2008 4:31 am
Let me try, we have to find out value of x.

Statement 1 : 200 x = 400 y -> x = 2y. Not Suff

Statement 2 - xy = n^2. Not Suff. (we dont have n and y)

Combine 1 and 2. - 2x*x = n^2 -> 2x^2 = n^2 -> x = n/sqrt(2). still Not Suff. (we dont have n)

Answer E.