ds from paper test ---percentage, algebra

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ds from paper test ---percentage, algebra

by wawatan » Thu May 29, 2008 8:14 pm
After winning 50 percent of the first 20 games it
played, Team A won all of the remaining games it
played. What was the total number of games that
Team A won?

(1) Team A played 25 games altogether.
(2) Team A won 60 percent of all the games it played

stuck between A and D.

will post OA later.

please post explanation . thanks
Source: — Data Sufficiency |

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wawatan wrote:After winning 50 percent of the first 20 games it
played, Team A won all of the remaining games it
played. What was the total number of games that
Team A won?

(1) Team A played 25 games altogether.
(2) Team A won 60 percent of all the games it played

stuck between A and D.

will post OA later.

please post explanation . thanks
We can create the following equation to see that (2) is also sufficient:

Total games won = games won in 1st 20 + remaining games won

let x = remaining games after the first 20

60%(20 + x) = 50%(20) + 100%(x)

We can solve for x, which means we can solve for total # of games won.
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by amitansu » Thu May 29, 2008 11:01 pm
Ans D here.

From 1: it's very evident.so sufficient.


From 2: (x-20)+10=.6x (assume x =total no. of games)

solve for x.so sufficient.