Gmatprep question

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Source: — Problem Solving |

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by pepeprepa » Sun Aug 10, 2008 8:45 am
(9)=3*9
(6)=6/2
(9)*(6)=81

The only one which gives 81 is (27):
(27)=27*3=81 because 27 is odd so we use the formula (m)=3m

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by [email protected] » Sun Aug 10, 2008 8:49 am
Thanks for the reply but I am still unclear please can you explain further?

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by pepeprepa » Sun Aug 10, 2008 8:56 am
9 is odd so we have to use the formula for odd numbers: (m)=3m
Now we can calculate: (9)=3*9=27
6 is even so we have to use the formula for even numbers (m)=m/2
Now we can calculate: (6)=6/2=3
What they asked us is the value of (9)*(6). We have the values of each one so we only have to multiply them.
(9)*(6)=27*3=81

Now we have a list of (m) numbers some are even, some are odd, when they are odd you do (m)=3m and when they are even you (m)=m/2
You can calculate all of them and find the result for each one, the result which indicates you the right answer is the result of (9)*(6), I mean 81.
The only one which gives 81 is (27):
(27)=27*3=81 because 27 is odd so we use the formula (m)=3m

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by [email protected] » Sun Aug 10, 2008 9:01 am
Great thanks very much!!