GMAT Prep: Functions

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GMAT Prep: Functions

by RM » Thu Jun 28, 2007 7:35 am
For all positive integers m, Fn(m) = 3m when m is odd and Fn(m) = (1/2)m when m is even. Which of the following is equivalent to Fn(9) * Fn(6)?

A. 81
B. 54
C. 36
D. 27
E. 18

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by mschling52 » Thu Jun 28, 2007 8:09 am
Is it A?

Fn(9) = 3*9 = 27, since 9 is odd
Fn(6) = (1/2)*6 = 3, since 6 is even

27*3 = 81

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by moneyman » Thu Jun 28, 2007 9:20 am
Is it A??
Maxx

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by mikeclarke44 » Sat Jul 07, 2007 11:04 am
No the answer is 27
9*6 = 54 which is even so you preform the (F) 1/2 *m

I don't follow this either, it seems it should be 81.

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by sudhirsk » Sat Jul 07, 2007 12:33 pm
I think the answer is function of 27.
3* 27 = 81. since 27 is odd.

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by manred » Tue Jul 24, 2007 8:22 pm
The answer is A.

Fn(9) = 3*9 = 27, since 9 is odd
Fn(6) = (1/2)*6 = 3, since 6 is even

Fn(9)*Fn(6) = 27*3 = 81

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by beny » Tue Jul 24, 2007 8:46 pm
I got this question when I was prepping for GMAT also. I was positive the answer was A (81), but GMAT prep said the answer was D (27). No explanation to the answer, thanks GMATPrep!