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Hei
 
 

Kaplan Preimer 2008 (Diagnostic)

by Hei Sat Aug 11, 2007 8:27 pm

Data Sufficient
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Faith 26
 
 

by Faith 26 Sun Aug 12, 2007 9:57 am

I think the answer is C.

Statement (1) tells us that [U] denotes inverse of a number. But this will not hold true if a=1.

Statement (2) tells that a is not equal to 1.

Both statements together helps us get the answer.
Hei
 
 

by Hei Mon Aug 13, 2007 4:54 pm

Faith 26 Wrote:I think the answer is C.

Statement (1) tells us that [U] denotes inverse of a number. But this will not hold true if a=1.

Statement (2) tells that a is not equal to 1.

Both statements together helps us get the answer.


If we consider both statements, we will have:

a*a = 1 => a = -1 (because of statement #2, a cannot be -1). => [u] could be "*"
a+a = 1 => a = 0.5 => [u] could be "+"
a-a = 1 => false => [u] won't be "-" for sure.
a/a = 1 => true for any real number a => [u] could be "/"

Therefore, considering both statements tells us that [u] could be "*", "-" or "/", and so we cannot conclude what [u] donates.

Am I wrong?
Hei
 
 

by Hei Tue Aug 14, 2007 2:39 pm

Arrh, I mixed up ">1" with ">=1"...I wasn't awake at all.
Thanks!
ayang
ManhattanGMAT Staff
 
Posts: 42
Joined: Thu Jul 31, 2003 1:31 pm
 

Kaplan material

by ayang Tue Aug 14, 2007 4:49 pm

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