Percent DS

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Percent DS

by reddox » Sun Sep 02, 2012 8:26 am
From Princeton Review mock test. I get A and not the OA (D)...

Daniel wins 25 percent of the first eight card games that he plays. If he loses all of the remaining card games that he plays, what was the total number of games that Daniel lost?

(1) Daniel played 20 card games.

(2) Daniel lost 90 percent of the card games that he played.

https://adptesteng.princetonreview.com/G ... ce/1373740
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by GMATGuruNY » Sun Sep 02, 2012 8:53 am
reddox wrote:From Princeton Review mock test. I get A and not the OA (D)...

Daniel wins 25 percent of the first eight card games that he plays. If he loses all of the remaining card games that he plays, what was the total number of games that Daniel lost?

(1) Daniel played 20 card games.

(2) Daniel lost 90 percent of the card games that he played.
Daniel wins 25% of the first 8 games.
He does not win any games after the first 8.
Thus, the total number of games won = .25(8) = 2.

Statement 1: Daniel played 20 card games.
Total number of games lost = 20-2 = 18.
SUFFICIENT.

Statement 2: Daniel lost 90 percent of the card games that he played.
Thus, he won 10% of the games.
Since he won a total of 2 games, and 2 is 10% of 20, the total number of games played = 20.
Total lost = 20-2 = 18.
SUFFICIENT.

The correct answer is D.
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by reddox » Sun Sep 02, 2012 9:00 am
Oh damn. I didn't think of statement two that way.

Thanks Mitch!
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