At a school, there were 50 pupils from Club W and 40% less pupils from Club X. Some pupils joined Club X and the ratio of the number of pupils from Club W to the number of pupils from Club X became 5 : 4. How many pupils joined Club X?
| |
Club W |
Club X |
| Before |
50 |
30 |
| Change |
|
+ ? |
| After |
5 u |
4 u |
Number of pupils from Club X at first in percent
= 100% - 40%
= 60%
Number of pupils from Club X at first
= 60% x 50
=
60100 x 50
= 30
Number of pupils in Club W remains unchanged.
5 u = 50
1 u = 50 ÷ 5 = 10
Number of pupils from Club X in the end
= 4 u
= 4 x 10
= 40
Number of pupils joined Club X
= 40 - 30
= 10
Answer(s): 10
