At a school, there were 35 boys from Club V and 40% 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 5 : 4. How many boys from Club W left?
| |
Club V |
Club W |
| Before |
35 |
49 |
| Change |
|
- ? |
| After |
5 u |
4 u |
Number of boys from Club W at first in percent
= 100% + 40%
= 140%
Number of boys from Club W at first
= 140% x 35
=
140100 x 35
= 49
Number of boys in Club V remains unchanged.
5 u = 35
1 u = 35 ÷ 5 = 7
Number of boys from Club W in the end
= 4 u
= 4 x 7
= 28
Number of boys from Club W who left
= 49 - 28
= 21
Answer(s): 21
