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Sets

by Mjkourtis » Wed Jul 11, 2012 3:29 pm
Are at least 10% of people older than 65 employed in Country X?

(1) In Country X, 11.3% of the people are 65 or older.
(2) In Country X, of those 65 or older, 20% of men and 10% of women are employed.
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by Jim@StratusPrep » Wed Jul 11, 2012 3:40 pm
1) INSUFFICIENT - we don't care about the number of people just the percentage of those who are over 25.
2) SUFFICIENT - if 20% of the men and 10% of the women are unemployed then the total average must be between the two, or greater than 10%. Think weighted averages..

The answer is B.
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by alex.gellatly » Wed Jul 11, 2012 5:24 pm
Mjkourtis wrote:Are at least 10% of people older than 65 employed in Country X?

(1) In Country X, 11.3% of the people are 65 or older.
(2) In Country X, of those 65 or older, 20% of men and 10% of women are employed.
We are trying to establish if at least 10% of people over 65 are employed. Please note this question is only interested in % of people, so you do not need to know the actual number of people.

Statement 1: Although this tells use the percentage of people over the age of 65, it tells us nothing about the percent of this age group who are unemployed. This is insufficient.

Statement 2: This tells us that 20% of the men and 10% of the women over the age group are over 65. Lets say there is only 1 man and only 1 woman in the country. That would mean the countries average percentage who work over the age of 65 is: 20%+10%/2 = 15%, which is over 10%....so this statement is sufficient. You can plug in more numbers and find that their weighted average will always be over 10% because both of the weights are over 10%

The correct answer is B.