Math questions from any Manhattan Prep GMAT Computer Adaptive Test.
chirag.shah285
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CAT 3 Help

by chirag.shah285 Mon Mar 09, 2009 6:57 pm

If a^2 is not equal to b^2, what is the value of a - b/a^2 - b^2 ?

(1) 3^b + 2 = 81

(2) a = 3^2b - 3

Can someone explain how to work this out? Thanks
esledge
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Re: CAT 3 Help

by esledge Mon Mar 16, 2009 4:29 pm

Hi Chirag,

Can you please clarify a bit, perhaps by putting in parentheses? I think the statements must both be 3 to the power of all that follows the ^ sign, but just want to be certain.

Also for future posts, please make the Subject the first 5-8 words of the question itself, for easy searching by others. See our forum guidelines for more info.

In the meantime, here's a hint: a^2 - b^2 = (a - b)(a + b). Plug that back into the original question and rephrase as much as you can (manipulate/simplify and find the "kernel").

Another hint: Recognizing 81 as a certain power of 3 is important for (1).
Emily Sledge
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ManhattanGMAT
yousuf_azim
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Re: CAT 3 Help

by yousuf_azim Sat Aug 27, 2011 8:55 am

Dears,

What is ANS?

BR
jnelson0612
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Re: CAT 3 Help

by jnelson0612 Sat Oct 01, 2011 3:44 pm

mmrs151 Wrote:Dears,

What is ANS?

BR


It looks like C to me.
Jamie Nelson
ManhattanGMAT Instructor