What is Average Height? (GMATPrep)

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What is Average Height? (GMATPrep)

by RadiumBall » Sun Mar 27, 2011 7:31 am
What is Average Height of the n people in a certain group?

(1) The average height of the n/3 tallest people in the group is 6 feet 5/2 inches, and the average height of the rest of the people in the group is 5 feet 10 inches

(2) The sum of the heights of the n people is 178 feet 9 inches.
Source: — Data Sufficiency |

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by vineeshp » Sun Mar 27, 2011 8:00 am
OA is A? Explanation follows.


Stmt 1:

((n/3)* average1 + (2n/3) * average2) / n

N cancels out and hence we can get the answer.

Stmt 2:

Total / n. Cannot be solved to get the right value.

A.
Vineesh,
Just telling you what I know and think. I am not the expert. :)

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by HSPA » Sun Mar 27, 2011 8:01 am
B) is giving 178/n... we cannot use it as n is unknown

A) is okay

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by vineeshp » Sun Mar 27, 2011 8:02 am
Very happy to post in my 100th post that I got that one all wrong. Reworking. :)
Vineesh,
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by vineeshp » Sun Mar 27, 2011 8:07 am
Actually I am confused. How many people are there in the group? n or n is a subset of the group?

I intially thought n is the total number of people in the group and we get A. Straightforward.

But are there more people in n? "of the n people in a certain group" seems to suggest so. :S
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by RadiumBall » Sun Mar 27, 2011 8:17 pm
Cool did not think it is so cheap. OA: A

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by force5 » Mon Mar 28, 2011 12:02 am
i hope all doubts are gone. answer is A