GMATPrep Question - Either i am missing some thing or...

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GMATPrep Question - Either i am missing some thing or there is something wrong with the question. Please help.

Question: 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# multiplied by #6#?
a)81
b)54
c)36
d)27
e)18

OA: D

I chose A and while reviewing checked my answer numerous times but still my answer is A = 81

Please help!!!

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by abhisays » Mon Aug 08, 2011 1:48 am
You have to divide your answer by 3 because it is talking about some equivalent, so the answer should be 81/3 i.e 27.

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by GMATGuruNY » Mon Aug 08, 2011 2:26 am
krnverma wrote:GMATPrep Question - Either i am missing some thing or there is something wrong with the question. Please help.

Question: 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# multiplied by #6#?
a)#81#
b)#54#
c)#36#
d)#27#
e)#18#

OA: D

I chose A and while reviewing checked my answer numerous times but still my answer is A = 81

Please help!!!
You are indeed missing something very important: in the GMATPrep question, the function symbol appears in all of the answer choices. I've amended the question to reflect its original intent.

Since #m# = 3m when m is odd, #9# = 3*9 = 27.
Since #m# = (1/2)m when m is even, #6# = (1/2)*6 = 3.
Thus, #9# * #6# = 27*3 = 81.

Answer choice D:
Since #m# = 3m when m is odd, #27# = 3*27 = 81.

The correct answer is D.
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by bhavesh_09 » Mon Aug 08, 2011 2:30 am
hi,

question and answer choices are wrong.

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by krnverma » Mon Aug 08, 2011 2:37 am
Thank you Mitch.

Can't believe I missed it.

Even though this question was one of the first few questions of my practice test and I was comparatively less pressured, I still missed the symbol in the answer choices. What is funny but important is that I was so sure that I did the math right but still selected the wrong choice.

I guess this is a classic example of predictable wrong choice given in the answer choices.

I have to be more attentive.

Thanks again.