GMATPrep - Ratio

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GMATPrep - Ratio

by tennis_24_7 » Sat Jan 02, 2010 8:59 pm
The number of stamps that Kaye and Alberto had were in the ratio of 5:3 respectively. After Kaye gave Alberto 10 of her stamps the ratio of the number Kaye had to the number Alberto had was 7:5. After the gift, Kaye had how many more stamps than Alberto?

a) 20
b) 30
c) 40
d) 60
e) 90

Also: Any quick method to solve this question?

OA: C
=)
Source: — Problem Solving |

Newbie | Next Rank: 10 Posts
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by tejasvgowda » Sat Jan 02, 2010 9:50 pm
(5x-10)/(3x+10) = 7/5

solving above for x, x = 30. Kaye has (5x-10) ie 140 and Alberto has (3x+10) ie 100. So Kaye has 40 more than Alberto after the gift.