Question from GMAT Prep

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Question from GMAT Prep

by mpaudena » Fri Dec 26, 2008 1:26 pm
I've got Windows Vista and it doesn't allow me to view the explanations to the CAT tests that I've taken. I have a question. Any help would be greatly appreciated:

For all positive intergers m #m# = 3m when m is odd and 1/2m when m is even. Which of the following is equivalent to #9# x #6#?

My answer was 81 and they said the answer was 27. Any one know why? Thanks in advance.
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Re: Question from GMAT Prep

by Ian Stewart » Fri Dec 26, 2008 1:54 pm
mpaudena wrote:I've got Windows Vista and it doesn't allow me to view the explanations to the CAT tests that I've taken. I have a question. Any help would be greatly appreciated:

For all positive intergers m #m# = 3m when m is odd and 1/2m when m is even. Which of the following is equivalent to #9# x #6#?

My answer was 81 and they said the answer was 27. Any one know why? Thanks in advance.
The answer isn't 27; it's #27#, which is equal to 81. Notice that none of the answer choices are numbers - the function is applied in each answer choice. Easy trap to fall into!
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by mpaudena » Fri Dec 26, 2008 2:34 pm
Tricky. Thanks.

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by Ian Stewart » Fri Dec 26, 2008 3:23 pm
Definitely tricky. I'd add that GMATPrep doesn't have explanations no matter what operating system you're on, Vista or otherwise.