Amazing OA
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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.
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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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
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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- Ian Stewart
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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.
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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- Morgoth
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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.
Thanks
Thanks
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.. 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?
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?
Aiming High
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I guess you found a different example, but (-1/3)*(-7/3) = 7/9, not 7/3.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?
For online GMAT math tutoring, or to buy my higher-level Quant books and problem sets, contact me at ianstewartgmat at gmail.com
ianstewartgmat.com
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