GMAT Prep ?? (Ratio)

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GMAT Prep ?? (Ratio)

by dferm » Wed Aug 27, 2008 7:06 am
At a certain university, the ratio of the number of teaching assistants to the number of students in any course must always be greater than 3:80. At this university, what is the minimum number of students possible in a course that has 5 teaching assistants?

A. 130
B. 131
C. 132
D. 133
E. 134

Please provide explanation and strategy!!!

Thanks.

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by Suyog » Wed Aug 27, 2008 8:22 am
5/x > 3/80

400 > 3x

400/3 > x

133.333 > x

therefore the greatest possible integer value for x is 133.

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by pepeprepa » Wed Aug 27, 2008 9:40 am
3:80
You have 5 teachers so let's respect the ratio to see what is the number of students according to this ratio.
Cross multiplying:
5*80/3 = 133.3333333333................
So theorically if we want to respect the ratio of 3:80 when we have 5 professors we can have a maximum of 133 + 0.333... of a student.
Given they ask us the maximum in concrete terms, it is 133.
And not 134 because in that case we would be above the ratio of 3:80

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by LSB » Wed Aug 27, 2008 12:36 pm
I assume there is a typo in the Q. It is supposed to be maximum number of students. Min would be zero

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by jeffxujian » Wed Aug 27, 2008 1:09 pm
OA plZ! IMO D 2.

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by Shrinidhi » Wed Aug 27, 2008 2:43 pm
I think D - 133

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by dalwow » Thu Aug 28, 2008 11:57 am
I just divided 80/3 = 26.66...

So, that's the minimum # of students per aide. Then multiply 26.66 x 5 = 133.3 which is the minimum # of students for 5 aides.
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by dferm » Thu Aug 28, 2008 7:58 pm
Answer is D