At a school, there were 40 girls from Club Y and 40% less girls from Club Z. Some girls joined Club Z and the ratio of the number of girls from Club Y to the number of girls from Club Z became 5 : 4. How many girls joined Club Z?
| |
Club Y |
Club Z |
| Before |
40 |
24 |
| Change |
|
+ ? |
| After |
5 u |
4 u |
Number of girls from Club Z at first in percent
= 100% - 40%
= 60%
Number of girls from Club Z at first
= 60% x 40
=
60100 x 40
= 24
Number of girls in Club Y remains unchanged.
5 u = 40
1 u = 40 ÷ 5 = 8
Number of girls from Club Z in the end
= 4 u
= 4 x 8
= 32
Number of girls joined Club Z
= 32 - 24
= 8
Answer(s): 8
