Mark School had 730 pupils and Neave School had 20% more pupils. When an equal number of pupils left each school, the ratio of the pupils in Neave School to that in Mark School became 2 : 1. How many pupils were there in both schools in the end?

	Mark School	Neave School	Difference
Before	730		146
Change	- ?	- ?
After	2 u	1 u	1 u

Since an equal number of pupils left 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 Mark School and Neave School at first and in the end the same. 

Difference between the number of pupils in both schools at first
= 20% x 730
= ²⁰₁₀₀ x 730
= 146

Difference between the number of pupils in both schools in the end
= 2 u - 1 u
= 1 u

1 u = 146

Total number of pupils in both schools in the end
= 2 u + 1 u
= 3 u
= 3 x 146
= 438

Answer(s): 438