What is this?

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What is this?

by masuarezdl » Wed Jul 15, 2009 10:59 am
Alright, this question is just confusing... Any ideas?

For all positive integers m, [m]=3m when m is odd, and [m]=(1/2)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]

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by learnitboy » Wed Jul 15, 2009 11:07 am
is [27] = 3* 27 = 81 the answer?

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Re: What is this?

by Morgoth » Wed Jul 15, 2009 11:08 am
masuarezdl wrote:Alright, this question is just confusing... Any ideas?

For all positive integers m, [m]=3m when m is odd, and [m]=(1/2)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]
it simply says when m is odd that is 9 use [m] = 3m = [9] = 3*9 = 27

when m is even that is 6 use [m] = m/2 = 6/2 = 3

[9]*[6] = 27*3 = 81

a) [81] = odd = 81*3 = 243
b) [54] = even = 54/2 = 27
c) [36] = even = 36/2 = 18
d) [27] = odd = 27*3 = 81-----------------this is the answer
e) [18] = even = 18/2 = 9


Hence D.

Hope this helps.

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by masuarezdl » Wed Jul 15, 2009 11:10 am
learnitboy wrote:is [27] = 3* 27 = 81 the answer?
No, answer is d) 27... I had the same reasoning as you...

That would equal 3m x (1/2)m = 1.5m = 81... But that is not correct.

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by masuarezdl » Wed Jul 15, 2009 11:19 am
masuarezdl wrote:
learnitboy wrote:is [27] = 3* 27 = 81 the answer?
No, answer is d) 27... I had the same reasoning as you...

That would equal 3m x (1/2)m = 1.5m = 81... But that is not correct.
There we go... there was one step missing! thanks!