Is Y a fraction?

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Is Y a fraction?

by umaa » Thu Aug 27, 2009 5:07 pm
X,Y > 0 ,If X^3 = Y, is Y a fraction?

(1) X^2 is a fraction
(2) X >Y
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by ShikenO/kau » Thu Aug 27, 2009 6:03 pm
X,Y > 0 ,If X^3 = Y, is Y a fraction?

(1) X^2 is a fraction
(2) X >Y

Statement I:
x^2 is fraction means x not an integer and x is also a fraction.
So X^3 that is y is fraction number.
Hence sufficient.

Statement II:
X>y>X^3 is possible only if X<1
As x,Y>0, X ranges between 0 and 1
So both X and Y are sufficient.

The answer is D.

Please give the correct answer.

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by umaa » Thu Aug 27, 2009 6:13 pm
The answer is D.
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Re: Is Y a fraction?

by vikram_k51 » Thu Aug 27, 2009 11:42 pm
umaa wrote:X,Y > 0 ,If X^3 = Y, is Y a fraction?

(1) X^2 is a fraction
(2) X >Y
Will be D

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Re: Is Y a fraction?

by Ian Stewart » Tue Sep 01, 2009 10:08 am
umaa wrote:X,Y > 0 ,If X^3 = Y, is Y a fraction?

(1) X^2 is a fraction
(2) X >Y
Where is the question from? A fraction is an expression with a numerator and a denominator; sqrt(2)/2, 397/19, 8/2 and -Pi/1000 are all fractions. Whether something is a fraction depends on how it's written, not on its value. So the question is meaningless (as is Statement 1); of course y could be written as a fraction, but it could also be written as a decimal or in some other form.

I suspect that they meant one of two things - they're either asking whether y is between 0 and 1, or they're asking whether y is what is known as a 'rational number' (a number which can be expressed as a fraction with an integer numerator and denominator). Those are very different questions, and without some sort of psychic connection with the question designer, there's no way to figure out which question is intended. No real GMAT question would ever be worded as this question is.
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