DS question

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Source: — Data Sufficiency |

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by Rahul@gurome » Fri Nov 12, 2010 10:20 pm
Consider first (1) alone.
It says P/Q > 0.
So (P > 0 and Q > 0) or (P < 0 and Q < 0).
Since P and Q are integers, P/Q <= (PQ)^2.
Take any example, let P = 2, Q = 3. So P/Q is 2/3.
Now (PQ)^2 = (2*3)^2 = 36.
Next let P = -2 and Q = -3. So P/Q is 2/3 and (PQ)^2 = 36
So P/Q <= (PQ)^2.
Or (1) alone is sufficient to answer the question.
Next consider (2) alone.
Q < 0.
Take P = -1, Q = -1. So P/Q = - 1/-1 = 1.
(PQ)^2 = (1)^2 = 1.
So P/Q = (PQ)^2.
Next let P = 1 and Q = -1. So P/Q = - 1/1 = -1. Also (PQ) ^2 = (1 *-1) ^2 = 1.
Again P/Q < (PQ)^2.
In any case P/Q <= (PQ)^2.
So answer to the main question is No.

Or (2) alone is also sufficient.

The correct answer is hence (D).
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by selango » Sat Nov 13, 2010 1:04 am
What is the source of the question?

I am not convinced.Just bcoz we can prove a is >! b,it doesn't mean that the statement is sufficient.

There are 2 scenarios a<b and a=b which make both statements not sufficient.So far I haven't seen a problem like this in GMAT.

Am I missing anything?Please do comment.
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by TOPGMAT » Sat Nov 13, 2010 8:31 am
Agree with you Selango that E is the answer...
Rahul can you confirm ? We can have p=q=1

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by GMATGuruNY » Sat Nov 13, 2010 12:34 pm
vaibhavjha wrote:Given that P and Q are non-zero integers. Is P/Q > (PQ) ^2 ?

Stmt1: P/Q >0
Stmt2: Q<0

OA: D
This definitely is not a question that would appear on the GMAT. If P and Q are nonzero integers, the answer to the question "Is P/Q > (PQ)^2?" will always be NO. How can we divide two integers and get a quotient that is larger than the square of the product of the two integers? Thus, the information given in the two statements is irrelevant -- a situation that would never occur in a real DS question.
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