Math questions from any Manhattan Prep GMAT Computer Adaptive Test.
Tanweer
 
 

Spot The Median

by Tanweer Thu Jun 12, 2008 11:04 am

Given distinct positive integers 1, 11, 3, x, 2, 15, and 9, which of the following could be the median?
3
5
11
14
It cannot be determined from the given information.


The question came in my CAT 1. the answer says its " 5"

Can anyone explain How as i feel it cant be determined?

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imran.lakhani
 
 

by imran.lakhani Thu Jun 12, 2008 9:37 pm

Given the set and arranging it in increasing order we get Set{1, 2, 3, 9, 11, 15, x}, where x can be any number. Since the problem says "distinct positive interger" it is fair to assume that x>3. When x=4,5,6,7,8, x is the median, because it is in the middle of the set. When x>10, x cannot equal 9, because the values must be distinct, the median becomes 9, since 9 is the middle term. Therefore, scanning the answer choices only 5 is represented as what the median could be and since we said x would be the median when it equaled 4,5,6,7 or 8, that would be our answer.

Hope that helps.
Guest
 
 

by Guest Sat Jun 14, 2008 3:19 pm

Dear Imraan

Thanks for the nice explanation.

tan
RonPurewal
Students
 
Posts: 19744
Joined: Tue Aug 14, 2007 8:23 am
 

by RonPurewal Sun Jun 15, 2008 10:49 pm

imran.lakhani Wrote:Given the set and arranging it in increasing order we get Set{1, 2, 3, 9, 11, 15, x}, where x can be any number. Since the problem says "distinct positive interger" it is fair to assume that x>3. When x=4,5,6,7,8, x is the median, because it is in the middle of the set. When x>10, x cannot equal 9, because the values must be distinct, the median becomes 9, since 9 is the middle term. Therefore, scanning the answer choices only 5 is represented as what the median could be and since we said x would be the median when it equaled 4,5,6,7 or 8, that would be our answer.

Hope that helps.


nicely done.