At a school, there were 60 boys from Club V and 20% more boys from Club W. Some boys from Club W left and the ratio of the number of boys from Club V to the number of boys from Club W became 6 : 5. How many boys from Club W left?
| |
Club V |
Club W |
| Before |
60 |
72 |
| Change |
|
- ? |
| After |
6 u |
5 u |
Number of boys from Club W at first in percent
= 100% + 20%
= 120%
Number of boys from Club W at first
= 120% x 60
=
120100 x 60
= 72
Number of boys in Club V remains unchanged.
6 u = 60
1 u = 60 ÷ 6 = 10
Number of boys from Club W in the end
= 5 u
= 5 x 10
= 50
Number of boys from Club W who left
= 72 - 50
= 22
Answer(s): 22
