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rmyoungsc
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For all positive integers m....

by rmyoungsc Thu Aug 20, 2009 12:37 am

For all positive integers m, [m] = 3m when m is odd and [m] = (1/2)m when m is even. Which of the following is equivalent to [9] x [6] ?

a) 81
b) 54
c) 36
d) 27
e) 18


This one is bugging me

[editor: this problem has been transcribed incorrectly. please see one of the threads to which another poster has linked below. thanks.]
furtadovinod
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Re: For all positive integers m....

by furtadovinod Thu Aug 20, 2009 11:00 am

rmyoungsc Wrote:For all positive integers m, [m] = 3m when m is odd and [m] = (1/2)m when m is even. Which of the following is equivalent to [9] x [6] ?

a) 81
b) 54
c) 36
d) 27
e) 18


This one is bugging me


The answer should be 81 (a) because
[9] = 3*9 = 27 since m=9 is odd

[6] = (1/2)*6 = 3 since m=6 is even
So, 27*3 = 81.
What's the OA?
rmyoungsc
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Re: For all positive integers m....

by rmyoungsc Thu Aug 20, 2009 1:21 pm

OA is d) 27. I think this one is trickier than it seems somehow.
furtadovinod
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Re: For all positive integers m....

by furtadovinod Thu Aug 20, 2009 8:27 pm

rmyoungsc Wrote:OA is d) 27. I think this one is trickier than it seems somehow.


There are two other posts that discuss this very same problem.

for-all-positive-integers-m-gmat-prep-t3167.html

for-all-positive-integers-m-m-3m-when-t6073.html

It seems your answer choices are incorrect. They are missing a box[].
RonPurewal
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Re: For all positive integers m....

by RonPurewal Tue Sep 15, 2009 6:56 pm

furtadovinod Wrote:It seems your answer choices are incorrect. They are missing a box[].


thank you. yes, the original transcription was incorrect.

thanks for posting the other threads.