At a school, there were 30 children from Club L and 10% more children from Club M. Some children from Club M left and the ratio of the number of children from Club L to the number of children from Club M became 5 : 3. How many children from Club M left?
|
Club L |
Club M |
Before |
30 |
33 |
Change |
|
- ? |
After |
5 u |
3 u |
Number of children from Club M at first in percent
= 100% + 10%
= 110%
Number of children from Club M at first
= 110% x 30
=
110100 x 30
= 33
Number of children in Club L remains unchanged.
5 u = 30
1 u = 30 ÷ 5 = 6
Number of children from Club M in the end
= 3 u
= 3 x 6
= 18
Number of children from Club M who left
= 33 - 18
= 15
Answer(s): 15