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