At a school, there were 40 pupils from Club C and 20% more pupils from Club D. Some pupils from Club D left and the ratio of the number of pupils from Club C to the number of pupils from Club D became 5 : 2. How many pupils from Club D left?
| |
Club C |
Club D |
| Before |
40 |
48 |
| Change |
|
- ? |
| After |
5 u |
2 u |
Number of pupils from Club D at first in percent
= 100% + 20%
= 120%
Number of pupils from Club D at first
= 120% x 40
=
120100 x 40
= 48
Number of pupils in Club C remains unchanged.
5 u = 40
1 u = 40 ÷ 5 = 8
Number of pupils from Club D in the end
= 2 u
= 2 x 8
= 16
Number of pupils from Club D who left
= 48 - 16
= 32
Answer(s): 32
