GMAT PREP

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GMAT PREP

by bhumika.k.shah » Sun Apr 04, 2010 11:33 am
If x+y/z = -2, is x positive ?

(1) z is negative

(2) y is positive

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by eaakbari » Sun Apr 04, 2010 11:49 am
Stem
For x to be positive y<x and y> 0
or z<0


Statement one
It proves z is negative but then x could be positive or also x negative but lesser than y
Hence Insuff

Statement two
Clearly Insuff again applying previous logic

Combined
Since z is negative and y is positive a positive value of x could lead to - 2
then again if x <y and x <0 could also give same answer
Hence Insuff
IMO E

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by bhumika.k.shah » Sun Apr 04, 2010 11:53 am
is it possible for you to explain with #s?
eaakbari wrote:Stem
For x to be positive y<x and y> 0
or z<0


Statement one
It proves z is negative but then x could be positive or also x negative but lesser than y
Hence Insuff

Statement two
Clearly Insuff again applying previous logic

Combined
Since z is negative and y is positive a positive value of x could lead to - 2
then again if x <y and x <0 could also give same answer
Hence Insuff
IMO E

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by eaakbari » Sun Apr 04, 2010 12:02 pm
I see I may have interpreted the question as (x+y)/z but that does not change the answer.

Statement one

If x=4, y=12 and z =-2
Then 4 + -6 =-2
but if x = -1 and y=6 and z=-6
Answer is -2
Hence Insuff

Statement two
Take the same examples as before y is positive in both and it gives us different values.
Hence Insuff as x can be negative or positive

Combined
Same examples as before and yet x can be negative or positive

Hence Insuff
Therefore E

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by bhumika.k.shah » Sun Apr 04, 2010 1:01 pm
Okay now i am TOTALLY confused :(

The OA is E

eaakbari which answer of urs do u choose to stick on to now? :D

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by eaakbari » Sun Apr 04, 2010 8:10 pm
My answer was always E and Ill stick to it :wink: .

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by eaakbari » Sun Apr 04, 2010 8:11 pm
I did make a typo and type D instead of E but corrected that right away. Hope that didnt confuse youj