Gmat prep Test 1--This looks like the question is incorrect.

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by khurram » Tue May 27, 2008 6:23 am
Any clues to this one.

Thanks
khurram

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by AleksandrM » Tue May 27, 2008 9:37 am
I agree with you. There has to be a typo in this question, since the relationship of m to the expression is not given. It doesn't make any sense. Where hell are you supposed to park the "m" ?!

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by AleksandrM » Tue May 27, 2008 9:44 am
I think it was meant to read 3^4n + 2 divided by 10m.

This expression can be reduced to 81^n + 1 or 81^n. The remainder will be 1^n which is just 1, regardless of what n is. So, as long as you know wht m is, you can get the answer.

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by khurram » Tue May 27, 2008 11:30 am
the question should read +m
there is already a post about it as one of the two incorrect questions on gmat prep.

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by gmatinjuly » Wed May 28, 2008 6:34 am
I think the anser should be D that is each statemen is sufficuent to answer the questions.

1. m and n are both positive
2. 3 has a cyclic proprtty (last digit)
3^0 = 1
3^1 = 3
3^2 = 9
3^3 = 27
3^4 = 81
3^5 = 243
3^6 = 729
3^7 = ---7
3^8 = ----1

so 3^4n for all ns will give 1 as last digit ...
3^4n + 2 will be 3^2 3 ^6 etc and will always have last digit as 9
so remainer will always be 9 ......irrespective of value of m or n