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MCAT 4- Ratio of x to y?

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MCAT 4- Ratio of x to y?

by Diep » Sun Jul 19, 2009 8:30 am
What is the ratio of x to y?
(1) 5x=2y
(2) 2x=7y-8

Man answer: Statement (1) alone is sufficient but statement (2) alone is not sufficient

My answer: Both statements together are sufficient.
Explanation: (1)--> x=y=0 or x/y = 2/5
(2) --> x=y=0 does not work

What do you guys think? Do you have seen any similar problems in materials of GMAC?
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by Ian Stewart » Sun Jul 19, 2009 10:07 am
Every real GMAT question that deals with ratios will be restricted to positive quantities only. So if this were a real GMAT question, it would say in advance that x and y were greater than zero. Your analysis is correct; if there is no further information in the question stem, then S1 tells us that the ratio of x to y is either 2 to 5, or it's undefined (if both x and y are zero). It's not an exception you'll encounter on the real test, however.
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by brick2009 » Sun Jul 19, 2009 11:15 am
From
1) x/y = 2/5 -> answers the question.

So ur choices have to be between A & D

This eliminates C..there is no way u can end up with C.

2.) Is not sufficient, as you can get multiple x/y values..

Hence A is the answer..


I cant figure out how u ended up with C..when A was correct to begin with.. :roll:
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by Jazzy3113 » Tue Jul 21, 2009 12:37 pm
I am having trouble with the second equation. Why are you unable to get a ratio? The constant of 8 should have no effect on the ratio, right?
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