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answer wrong?-T*=3T

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answer wrong?-T*=3T

by jopup » Sat Jun 14, 2008 8:42 am
for all positive integers T, T*=3T when T is odd and T*=1/2T when T is even. Which of the following is equivalent to to 9*x6*

81

54

36

27

18

I chose 81 , why is it wrong??
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by Ian Stewart » Sat Jun 14, 2008 9:13 am
I think I remember this question...

As I recall, the answer choices are not as you've written them. They should be:

81*
54*
36*
27*
18*

Notice that each answer choice has the * function applied to it: choice A is not equal to 81!
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by anshul265 » Sat Jun 14, 2008 11:28 am
Makes sense. Now 27* becomes the answer.
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by babachal » Sat Jun 14, 2008 11:34 am
hi jopup, can u explain me please, how did u come up such consequence?
9*=27 rite?
6*=1/12
27x1/12=27/12=9/4?
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by beeparoo » Sat Jun 14, 2008 5:51 pm
Baba, your mistake is here:
babachal wrote:6*=1/12
It's not your fault though because the question stem is typed in an ambiguous way. For correctness, re-read as such:

...when T is odd and T*=(1/2)T
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by AleksandrM » Tue Jun 17, 2008 9:46 am
Hey,

9* x 6* = 56* = 56(1/2) = 27.

However,

9* = 3(9) = 27

6* = 6(1/2) = 3

27 x 3 = 81

And,

27* = 27(3) = 81

Are these all the same?
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by beeparoo » Tue Jun 17, 2008 4:31 pm
AleksandrM wrote:Hey,

9* x 6* = 56* (<-- This does not satisfy the question requirements, so it's incorrect.)
= 56(1/2) = 27.

However,

Everything after this point is GOOD.

9* = 3(9) = 27

6* = 6(1/2) = 3

27 x 3 = 81

And,

27* = 27(3) = 81

Are these all the same?
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by AleksandrM » Tue Jun 17, 2008 6:36 pm
Kool. Thanks.
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