Charlie School had 415 pupils and Ethan School had 40% less pupils. When an equal number of pupils joined each school, the ratio of the pupils in Ethan School to that in Charlie School became 3 : 2. How many pupils were there in both schools in the end?
|
Charlie School |
Ethan School |
Difference |
Before |
415 |
|
166 |
Change |
+ ? |
+ ? |
|
After |
3 u |
2 u |
1 u |
Since an equal number of pupils joined each school, the difference in the number of pupils at first and in the end between the 2 schools remains the same. Make the difference between the number of pupils in Charlie School and Ethan School at first and in the end the same.
Difference between the number of pupils in both schools at first
= 40% x 415
=
40100 x 415
= 166
Difference between the number of pupils in both schools in the end
= 3 u - 2 u
= 1 u
1 u = 166
Total number of pupils in both schools in the end
= 3 u + 2 u
= 5 u
= 5 x 166
= 830
Answer(s): 830