At a school, there were 10 girls from Club G and 20% more girls from Club H. Some girls from Club H left and the ratio of the number of girls from Club G to the number of girls from Club H became 5 : 4. How many girls from Club H left?
| |
Club G |
Club H |
| Before |
10 |
12 |
| Change |
|
- ? |
| After |
5 u |
4 u |
Number of girls from Club H at first in percent
= 100% + 20%
= 120%
Number of girls from Club H at first
= 120% x 10
=
120100 x 10
= 12
Number of girls in Club G remains unchanged.
5 u = 10
1 u = 10 ÷ 5 = 2
Number of girls from Club H in the end
= 4 u
= 4 x 2
= 8
Number of girls from Club H who left
= 12 - 8
= 4
Answer(s): 4
