Valen School had 300 students and Ivan School had 30% more students. When an equal number of students left each school, the ratio of the students in Ivan School to that in Valen School became 3 : 2. How many students were there in both schools in the end?

	Valen School	Ivan School	Difference
Before	300		90
Change	- ?	- ?
After	3 u	2 u	1 u

Since an equal number of students left each school, the difference in the number of students at first and in the end between the 2 schools remains the same.  Make the difference between the number of students in Valen School and Ivan School at first and in the end the same. 

Difference between the number of students in both schools at first
= 30% x 300
= ³⁰₁₀₀ x 300
= 90

Difference between the number of students in both schools in the end
= 3 u - 2 u
= 1 u

1 u = 90

Total number of students in both schools in the end
= 3 u + 2 u
= 5 u
= 5 x 90
= 450

Answer(s): 450