At a school, there were 72 boys from Club X and 25% less boys from Club Y. Some boys joined Club Y and the ratio of the number of boys from Club X to the number of boys from Club Y became 6 : 5. How many boys joined Club Y?
| |
Club X |
Club Y |
| Before |
72 |
54 |
| Change |
|
+ ? |
| After |
6 u |
5 u |
Number of boys from Club Y at first in percent
= 100% - 25%
= 75%
Number of boys from Club Y at first
= 75% x 72
=
75100 x 72
= 54
Number of boys in Club X remains unchanged.
6 u = 72
1 u = 72 ÷ 6 = 12
Number of boys from Club Y in the end
= 5 u
= 5 x 12
= 60
Number of boys joined Club Y
= 60 - 54
= 6
Answer(s): 6
