X > Y ?

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X > Y ?

by Hope700 » Wed Nov 05, 2008 1:54 pm
is X>Y?

I (x)/(3y) > 1/3

II -x+p < -y+p


I chose D

From I we obtain 3x > 3y

then we divide all by 3 and we get

x > y So it is suff

II -x < - y or x>y

Then again is suff

However the correct answer says that only B is correct and the explanation says that with St 1 X could be either positive or negative and that means it is not sufficient

I don't quite understand the explanation any hint that you provide would be very helpful
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Re: X > Y ?

by jimmiejaz » Wed Nov 05, 2008 4:51 pm
Hope700 wrote:is X>Y?

I (x)/(3y) > 1/3

II -x+p < -y+p


I chose D

From I we obtain 3x > 3y

then we divide all by 3 and we get

x > y So it is suff

II -x < - y or x>y

Then again is suff

However the correct answer says that only B is correct and the explanation says that with St 1 X could be either positive or negative and that means it is not sufficient

I don't quite understand the explanation any hint that you provide would be very helpful
Yes, the ans will be B.
remember never multiply with a variable in an inequality unless you dont know the sign of the variable.
given as per the choice..
x/3y>1/3.
we can write it as x/y>1 but cant as x>y coz suppose y is negative then multiplying with a negative number changes the sign of the inequality.
So B is suff. A is insuff as its does not tell if X or Y is positive or vice versa.

Hope it helps.....