GPrep Overlapping Sets Question

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GPrep Overlapping Sets Question

by gkumar » Sun Oct 18, 2009 3:20 pm
GPrep Question
Are at least 10% of people 65 and older employed?
1) 11.3% of population is 65 or over
2) Of those 65 and older, 20% of men and 10% of women are employed.

I tried to make a double matrix for this question, but instead of 4 factors, this question has SIX factors (younger or older than 65, employed and unemployed, and men and women), so I wasn't sure how to tackle this problem.

OA is B

Please comment on a fast, efficient method to solve this problem. Thanks.
Source: — Data Sufficiency |

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by gkumar » Sun Oct 18, 2009 3:23 pm
I think this might have to deal with weighted averages rather than overlapping sets, but I am not sure either.

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by gkumar » Sun Oct 18, 2009 3:51 pm
Ugh, I had a momentary lapse.

Testing extremes. If men = 0, then women as 10% acts as a floor for the employed 65 and older population. So the result can never be less than 10%. So B is sufficient.