GPrep Ques

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by eagleeye » Sun May 13, 2012 6:04 pm
Hi Ranjeet75:

All can be true.
When evaluating questions like this keep in mind that fractional values become smaller when they are squared or quadrupled. The correct answer is all three. Let me give you specific examples.

For I:

Let x = 100, y = 5, z= 1; then y^2 = 25, z^4 = 1 and we have x>y^2>z^4 and x>y>z.
So I can be true.

For II:
Let x = 0.3 ; y = 0.4; z = 0.5 ; then y^2 = 0.16 ; z^4 = 0.0625 and we have x>y^2>z^4 and z>y>x.
So II can be true.

For III:
Let x= 100 ; y = 0.4 ; z = 0.5 ; then y^2 = 0.16 ; z^4 = 0.0625 and we have x>y^2>z^4 and x>z>y
So III can be true.

Hence the final answer is I, II, III

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by Anurag@Gurome » Sun May 13, 2012 8:56 pm
ranjeet75 wrote:Please provide explanation
(I) x > y^2
  • Certainly for integer values of x and y, x is always greater than y. But what about fractional values> f y is a fraction then y^2 is < y. Now always there is a fraction x, such that y > x > y^2. Thus for fractional values x may be less than y. Therefore regarding the relation between x and y all of the options could be true.
(II) x > z^4
  • Same logic as above.
(II) y^2 > z^4
  • This directly implies y > z^2. Now again apply same logic as above.
The correct answer is E.
Anurag Mairal, Ph.D., MBA
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