Overlooking the obvious

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Overlooking the obvious

by capnx » Wed Nov 18, 2009 3:47 pm
Is at least 10% of the population in Country X who are 65yrs old or older employed?

1. In country X, 11.3% of the population is 65yrs old or older
2. In country X, of the population 65yrs old or older, 20% of the men and 10% of the women are employed.

[spoiler]OA: B 20%m+10%w > 10%population (which is m+w)

I keep messing up these easy questions. The question is not hard, but I just don't think the concept of "Total population = men + women". Any suggestions?[/spoiler]

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by palvarez » Wed Nov 18, 2009 4:11 pm
In over lapped sets, men and women are complementary.


I think, you should maintain a set of notes that track these kind of issues.

There is another trap GMAT deployes wrt overlapping sets.

Q: 20 percent of employees at company X work have master degrees; of these, 15 percent of them work on laptops. How many of those who have masters degree work on laptops.

(1) 100 employees have bald heads
(2) 40 percent of employees have bald heads.

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by grockit_jake » Thu Nov 19, 2009 4:52 pm
You can do venn diagram or L matrix for these. I prefer L visually since you can add the totals vertically and horizontally without crossing your eyes.

Also remember that when you have 2 groups with an overlap,

Total = (All in A) + (All in B) - 2*(both)
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