Amazing OA

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Amazing OA

by Morgoth » Thu Oct 09, 2008 9:23 am
Dont spend too much time on this because I think the question is just plain stupid or am I wrong? I just need a second opinion. By the way OA is B.
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by vivek.kapoor83 » Thu Oct 09, 2008 9:28 am
IMO E
a. xy =35,it can be in 2 condn. x,y both -ve or both +ve. . Insuff
b. x = y-2..Insuff
Taking a & b together.
35 has 2 factors -both are prime =7,5
and if both are positive, x=5 and y-7, b satisfies.
x = -7 , y = -5 (taking both -ve)
b satisfies...
SO.IMO E.

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by Morgoth » Thu Oct 09, 2008 9:34 am
Ok noted your reasoning,

Statement (1)

xy = 35

if we know xy is 35 , isnt it sufficient that xy is not less than 1, So sufficient.

what do you think.

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by Gmatss » Thu Oct 09, 2008 9:52 am
shouldn't the QA be A???
They stated x and y are both negative numbers..
even if you take a fractional value for 1st statment answer still comes out no. ex (-5/2 * -14)
where is the source from? thanks

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by Ian Stewart » Thu Oct 09, 2008 2:43 pm
I'm also curious where the question is from.

Clearly Statement 1 is sufficient. If you know the value of xy, you can obviously decide whether xy is less than 1.

Statement 2 is not sufficient; if you choose a value of y very close to zero (-1/3, for example, so that x = -7/3), xy can be less than 1, while if you choose a small enough (very negative) value for y, xy can be as large as you want. If we had more information- if we knew, for example, that x and y were both negative integers- this information might be sufficient, but it is not sufficient as stated.

So the answer is A.
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by Morgoth » Thu Oct 09, 2008 3:14 pm
Thanks Ian, I really appreciate your response. The question is from one of the gmat test prep company in India. I took one of their tests today and was a total waste of time. They obviously have no idea about what GMAT is all about.

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by krazy800 » Mon Oct 13, 2008 9:35 am
.. Ian I didn't understand ur statemenrt...


Statement 2 is not sufficient; if you choose a value of y very close to zero (-1/3, for example, so that x = -7/3), xy can be less than 1,

from the above xy = 7/3 >1 ..

am I missing something?
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by krazy800 » Mon Oct 13, 2008 9:40 am
k I got it.. Thanks Ian

if Y=-.0001
X=-2.0001


then XY<1.. so statement 2 is not sufficient..

Thanks Again..
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by Ian Stewart » Tue Oct 14, 2008 12:51 am
krazy800 wrote:.. Ian I didn't understand ur statemenrt...


Statement 2 is not sufficient; if you choose a value of y very close to zero (-1/3, for example, so that x = -7/3), xy can be less than 1,

from the above xy = 7/3 >1 ..

am I missing something?
I guess you found a different example, but (-1/3)*(-7/3) = 7/9, not 7/3.
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