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