At a school, there were 20 girls from Club W and 40% less girls from Club X. Some girls joined Club X and the ratio of the number of girls from Club W to the number of girls from Club X became 4 : 3. How many girls joined Club X?
|
Club W |
Club X |
Before |
20 |
12 |
Change |
|
+ ? |
After |
4 u |
3 u |
Number of girls from Club X at first in percent
= 100% - 40%
= 60%
Number of girls from Club X at first
= 60% x 20
=
60100 x 20
= 12
Number of girls in Club W remains unchanged.
4 u = 20
1 u = 20 ÷ 4 = 5
Number of girls from Club X in the end
= 3 u
= 3 x 5
= 15
Number of girls joined Club X
= 15 - 12
= 3
Answer(s): 3