Number Systems

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Number Systems

by sukhman » Wed Oct 16, 2013 9:59 am
For all positive integers m, (m) = 3m when m is odd and (m) = ½ m when m is even, which of the following is equivalent to (9)*(6)?
(81) (54) (36) (27) (18)
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by Brent@GMATPrepNow » Wed Oct 16, 2013 10:36 am
sukhman wrote:For all positive integers m, (m) = 3m when m is odd and (m) = ½ 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)
9 is odd, so (9) = 3x9 = 27
6 is even, so (6) = 6/2 = 3
So, (9) x (6) = 27 x 3 = 81

BE CAREFUL, the answer choices are as follows:
A) (81)
B) (54)
C) (36)
D) (27)
E) (18)
[as opposed to 81, 54, 36, etc]


So, which of the 5 answer choices is equivalent to 81?

Since 27 is odd, (27) = 3 x 27 = 81

So, the correct answer is D

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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