At a school, there were 36 girls from Club Y and 25% 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 6 : 5. How many girls joined Club Z?
| |
Club Y |
Club Z |
| Before |
36 |
27 |
| Change |
|
+ ? |
| After |
6 u |
5 u |
Number of girls from Club Z at first in percent
= 100% - 25%
= 75%
Number of girls from Club Z at first
= 75% x 36
=
75100 x 36
= 27
Number of girls in Club Y remains unchanged.
6 u = 36
1 u = 36 ÷ 6 = 6
Number of girls from Club Z in the end
= 5 u
= 5 x 6
= 30
Number of girls joined Club Z
= 30 - 27
= 3
Answer(s): 3
