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Source: — Data Sufficiency |
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by mals24 » Mon Sep 22, 2008 4:13 am
IMO E

St 1 says 14x^2=3
ie x^2 = 3/14
x = +-sq rt (3/14)---INSUFF

St 2 says y^2=1
y=+-1----INSUFF

Combining i & 2

If x and y have the same sign then xy>x^2*y^2
If x and y have opposite signs the xy<x^2*y^2

Hence the answer is E
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by beater » Mon Sep 22, 2008 7:47 am
Anyone with a different approach?
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by tendays2go » Mon Sep 22, 2008 8:05 am
(E) ?

logic:
Is xy > x^2y^2?
(1) 14x^2 = 3
(2) y^2 = 1
-------------------------------
RHS => x^2y^2 = (x^2)^y^2 = (3/14)^sq(y) = 3/14 =.21

now, xy = x or -x (depending upon value of y)
now RHS is always greater than -x i.e. LHS < RHS
thus, LHS when, x =sqrt(3/14) =.41 i.e. LHS > RHS

thus, answer is both stmts not sufficient.
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by Sachindh » Mon Sep 22, 2008 9:22 pm
Answer should be "E" simply because from both the statement gives the value of x and y be + or - respectively.
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