positive integers

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positive integers

by nidhis.1408 » Thu Nov 17, 2011 11:38 am
For all positive integers m, m=3m when m is odd and m = 1/2m when m is even. Which of the following is equivalent to 9*6?

1. 81
2. 54
3. 36
4. 27
5. 18

I am just not able 2 comprehend the problem. Of course i answered it wrong!
i need some good explanation .

ps- small correction in the question
Last edited by nidhis.1408 on Thu Nov 17, 2011 11:50 am, edited 1 time in total.
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by shankar.ashwin » Thu Nov 17, 2011 11:44 am
FOr all odd m, m =3m

Therefore, 9 = 3(9) = 27

For all even m, m = m/2

Therefore 6 = 6/2 = 3.

9*6 = 27*3 = 81 A IMO

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by GMATGuruNY » Thu Nov 17, 2011 11:48 am
The problem has been transcribed incorrectly. Check here:

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