At a school, there were 10 boys from Club T and 10% more boys from Club U. Some boys from Club U left and the ratio of the number of boys from Club T to the number of boys from Club U became 5 : 3. How many boys from Club U left?
| |
Club T |
Club U |
| Before |
10 |
11 |
| Change |
|
- ? |
| After |
5 u |
3 u |
Number of boys from Club U at first in percent
= 100% + 10%
= 110%
Number of boys from Club U at first
= 110% x 10
=
110100 x 10
= 11
Number of boys in Club T remains unchanged.
5 u = 10
1 u = 10 ÷ 5 = 2
Number of boys from Club U in the end
= 3 u
= 3 x 2
= 6
Number of boys from Club U who left
= 11 - 6
= 5
Answer(s): 5
