At a school, there were 10 girls from Club V and 30% more girls from Club W. Some girls from Club W left and the ratio of the number of girls from Club V to the number of girls from Club W became 5 : 2. How many girls from Club W left?
| |
Club V |
Club W |
| Before |
10 |
13 |
| Change |
|
- ? |
| After |
5 u |
2 u |
Number of girls from Club W at first in percent
= 100% + 30%
= 130%
Number of girls from Club W at first
= 130% x 10
=
130100 x 10
= 13
Number of girls in Club V remains unchanged.
5 u = 10
1 u = 10 ÷ 5 = 2
Number of girls from Club W in the end
= 2 u
= 2 x 2
= 4
Number of girls from Club W who left
= 13 - 4
= 9
Answer(s): 9
