Is x > y? (1) sqrt x > y (2) x^3 > y

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by puneetkhurana2000 » Fri Dec 14, 2012 12:48 am
Statement 1) sqrt x > y ..In GMAT you can safely assume that only real numbers are there, so x must be positive.

Case 1) sqrt 16 > 3 , so 16 > 3 Yes
Case 2) sqrt 1/4 > 1/3 , so 1/4 > 1/3 No

Not Sufficient!!!

Statement 2) x^3 > y

Case 1) 2^3 > 1 , so 2 > 1 Yes
Case 2) (-1/2)^3 > -1/4, so -1/2 > -1/4 No

Not Sufficient!!!

Together we have x is positive and as x^3 > y, we must have x > y.

Answer C

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by varun289 » Fri Dec 14, 2012 12:58 am
hi khurana , is any other way more easier ? HIt and trial is least preferred

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by puneetkhurana2000 » Fri Dec 14, 2012 1:08 am
Sorry Varun, can't think of any other way. You need to ask Experts.

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by GMATGuruNY » Fri Dec 14, 2012 4:31 am
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