At a school, there were 30 pupils from Club V and 10% more pupils from Club W. Some pupils from Club W left and the ratio of the number of pupils from Club V to the number of pupils from Club W became 5 : 4. How many pupils from Club W left?
| |
Club V |
Club W |
| Before |
30 |
33 |
| Change |
|
- ? |
| After |
5 u |
4 u |
Number of pupils from Club W at first in percent
= 100% + 10%
= 110%
Number of pupils from Club W at first
= 110% x 30
=
110100 x 30
= 33
Number of pupils in Club V remains unchanged.
5 u = 30
1 u = 30 ÷ 5 = 6
Number of pupils from Club W in the end
= 4 u
= 4 x 6
= 24
Number of pupils from Club W who left
= 33 - 24
= 9
Answer(s): 9
