Gmat Prep Ques

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Gmat Prep Ques

by dferm » Wed Nov 28, 2007 10:06 am
The sum of the integers in a list is the same as the sum of the integers in list T. Does S contain more integers than T?

(1) The average (arithmetic mean) of the integers in S is less than the average of the integers in T.

(2) The median of the integers in S is greater than the median of the integers in T.

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by ri2007 » Wed Nov 28, 2007 12:38 pm
ans should be A

Mean = Sum / No of terms.

Since the sum is the same for both the sets and the avg of one is less than the other. The one with the lower avg will have greater terms.

pls confirm

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Gmat DS

by dferm » Wed Nov 28, 2007 1:16 pm
Ur correct again but why is it A and not B since we don't really have any information in either of the two.

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by Patrick_GMATFix » Wed Jul 21, 2010 6:04 am
B cannot be right because although statement 2 tells us which median is greater we have no way to tell which list has more integers. The lists could be S={1,3,4} and T={0,1,7} (S has greater median but sum of lists are equal). In this case S does not contain more integers than T. However the lists could instead be S={0,3,3,4} and T={0,1,9}. In this case S contains more integers than T.

Thus from the 2nd statement we cannot determine whether S contains more values.

The official answer is A, though I have a problem with statement 1 being sufficient. In effect, I think that the official answer assumes that the sum is positive, something we actually don't know.

Anyway, a fuller discussion and video solution can be found at GMATPrep Question 1335. To create drills with similar questions, set topic='Sets & Groups and Statistics' and difficulty='600-700 & 700+' in the Drill Generator.

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