At a school, there were 40 children from Club S and 30% less children from Club T. Some children joined Club T and the ratio of the number of children from Club S to the number of children from Club T became 5 : 4. How many children joined Club T?
|
Club S |
Club T |
Before |
40 |
28 |
Change |
|
+ ? |
After |
5 u |
4 u |
Number of children from Club T at first in percent
= 100% - 30%
= 70%
Number of children from Club T at first
= 70% x 40
=
70100 x 40
= 28
Number of children in Club S remains unchanged.
5 u = 40
1 u = 40 ÷ 5 = 8
Number of children from Club T in the end
= 4 u
= 4 x 8
= 32
Number of children joined Club T
= 32 - 28
= 4
Answer(s): 4