GMAT prep

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GMAT prep

by taneja.niks » Sun Jul 25, 2010 12:22 am
For al positive integers m, m=3m when mis odd and m=1/2m when m is even which of the following is equvalent to 9*6

81
54
36
27
18

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by selango » Sun Jul 25, 2010 12:25 am
m=3m,when m is odd

m=1/2m,when m is even

9*6

m=9 is odd,m=27

m=6 is even,m=3

27*3=81

Pick A
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by taneja.niks » Sun Jul 25, 2010 12:29 am
yeah buddy i got the same one........ but the answer according to the gmat prep........ is 27

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by selango » Sun Jul 25, 2010 12:33 am
taneja,

I think something is missing in the question.Can u pl check it again?
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by taneja.niks » Sun Jul 25, 2010 12:37 am
nope buddy the question is exactly same the same thing baffled me as this was my first question in the practice test... and i ws sure i made the right answer....

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by selango » Sun Jul 25, 2010 12:37 am
I remember this question.There must be one symbol like []

[m]=3m,when m is odd

[m]=1/2m,when m is even

[9]=27

[6]=3

[9]*[6]=81

81 is expressed by[27] (since 27 is odd [27]=81)

Pick D

This is the question in GMATPREP ?rt?
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by taneja.niks » Sun Jul 25, 2010 12:43 am
Yes u r right buddy one from GMAT prpe only.......... thts relly tricky..:-)

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by selango » Sun Jul 25, 2010 1:05 am
Dude..u missed the symbol in the question..tats why it leads to diff answer..
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by getso » Tue Jul 27, 2010 9:49 am
selango wrote:I remember this question.There must be one symbol like []

[m]=3m,when m is odd

[m]=1/2m,when m is even

[9]=27

[6]=3

[9]*[6]=81

81 is expressed by[27] (since 27 is odd [27]=81)

Pick D

This is the question in GMATPREP ?rt?
I didn't get the last step i.e how 81 is expressed as 27.

Could you please explain??

Thanks,
Shobha

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by selango » Tue Jul 27, 2010 10:19 am
Because the answer options are expressed as symbol[]

[9]*[6]=81

81 is odd..How to express 81 in symbol [] form?

[m]=3m,when m is odd

[m]=81

[m]=3*27

-->m=27

[27]

Hope this clarify..
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by saurabhmahajan » Wed Jul 28, 2010 5:03 am
Friends can it be this way ?
9*6 =54
so m is even and therefore m/2.
therefore 54/2= 27
Thanks and regards,
Saurabh Mahajan

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by rahul goyal » Mon Aug 09, 2010 12:48 am
selango wrote:m=3m,when m is odd

m=1/2m,when m is even

9*6

m=9 is odd,m=27

m=6 is even,m=3

27*3=81

Pick A
Thanks. Easy way to solve the problem.

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by Taran » Wed Oct 19, 2011 10:24 pm
This is how i solved it. m can be either odd or even but not both at the same time.

Lets take m=odd. So in 9 x 6, m is 9. Therefore 9x3=27 and 27x6=162. Since 162 is not a given answer, m cannot be odd and therefore must be even (m is a positive integer).

If m is even, then in 9x6, m is 6. so 1/2 x 6 = 3 and 9 x 3 = 27. 27 also exist in our answer options.

Therefore, answer is 27 or D.

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by sl750 » Fri Oct 21, 2011 10:44 am
Both the question and the answer have been wrongly transcribed. The original poster seemed pretty confident he/she had it transcribed correctly