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sanjeethbm
Students
 
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Joined: Wed Dec 31, 1969 8:00 pm
 

DS Problem of employed students.

by sanjeethbm Tue Jun 14, 2011 12:00 am

How many of the 42 people in the group are employed students?
1. 29 of the 42 people are employed.
2. 24 of the 42 people are students.

My Approach
Since we need to find employed students I consider this number to be as 'n'.
29 of 42 are employed = 29 - n
24 of 42 are students = 24 - n

Adding it up
29 - n + 24 - n + n = 42
=> n = 13
My answer is C, however the correct ans is E.
Please let me know if my approach is right.

- Sanjeeth
RonPurewal
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Re: DS Problem of employed students.

by RonPurewal Tue Jun 14, 2011 7:27 am

sanjeethbm Wrote:My answer is C, however the correct ans is E.
Please let me know if my approach is right.


hmm?
you got the wrong answer, so you know that the answer to "is my approach right?" is no.

what you're missing is the possibility that the group contains people who are neither students nor employed. (in general, you must consider "neither a nor b" a possibility in any overlapping-set problem, unless the problem statement specifically excludes such a possibility.)
if you had used the overlapping-set grid described in our word translations strategy guide, it would have been easier for you to realize that this is a possibility.
sanjeethbm
Students
 
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Re: DS Problem of employed students.

by sanjeethbm Wed Jun 15, 2011 2:06 am

Now I know which is the missing link!

Thank you Ron!
jnelson0612
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Re: DS Problem of employed students.

by jnelson0612 Sun Jun 19, 2011 11:34 pm

:-)
Jamie Nelson
ManhattanGMAT Instructor