Wht 2do whn ans can be found w/t 1 & 2?

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Wht 2do whn ans can be found w/t 1 & 2?

by ritula » Sun Sep 21, 2008 10:20 pm
I came across a problem where the solution could be found by solving the given equation itself. so both eq 1 & 2 were not required at all.
In such a situation , wht should be the answer?
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Source: — Data Sufficiency |

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by mals24 » Mon Sep 22, 2008 3:58 am
If possible can you post the question.
Because if you are able to solve it using the data in the question itself it wouldn't be a Data Suff question it would be a problem solving instead.
But if you did face a situation like this the answer would be E both sts together and alone are not suff.

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by Ian Stewart » Mon Sep 22, 2008 11:13 am
mals24 is entirely correct that you will never, ever see such a question on a real GMAT. In real GMAT Data Sufficiency, you can never answer the question in the stem without more information. If you think you can, you've misunderstood the question. You always need at least one of the statements. That said, you may find the occasional question in test prep books that does not observe this rule, but don't take that to mean anything about the real thing.
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The question

by ritula » Mon Sep 22, 2008 9:14 pm
The question is as under:
For integers x and y , x=y/6 +1 . Is xy even?

(1) y+1/5 =x
(2) y/x is not odd

Explanation is y=6x-6
xy=6x^2-6x
Becasue x is an integer, 6x^2-6x is always even.

The OA was D.
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Re: The question

by Ian Stewart » Tue Sep 23, 2008 2:49 am
ritula wrote:The question is as under:
For integers x and y , x=y/6 +1 . Is xy even?

(1) y+1/5 =x
(2) y/x is not odd

Explanation is y=6x-6
xy=6x^2-6x
Becasue x is an integer, 6x^2-6x is always even.

The OA was D.
Yes, I agree that you can answer this without needing either of the statements- y is clearly divisible by 6, so y must be even, and therefore xy must be even. So this is not a well-designed question. Where did you find it?
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