At a school, there were 30 pupils from Club K and 40% less pupils from Club L. Some pupils joined Club L and the ratio of the number of pupils from Club K to the number of pupils from Club L became 5 : 4. How many pupils joined Club L?
| |
Club K |
Club L |
| Before |
30 |
18 |
| Change |
|
+ ? |
| After |
5 u |
4 u |
Number of pupils from Club L at first in percent
= 100% - 40%
= 60%
Number of pupils from Club L at first
= 60% x 30
=
60100 x 30
= 18
Number of pupils in Club K remains unchanged.
5 u = 30
1 u = 30 ÷ 5 = 6
Number of pupils from Club L in the end
= 4 u
= 4 x 6
= 24
Number of pupils joined Club L
= 24 - 18
= 6
Answer(s): 6
