Bobby School had 350 students and Ivan School had 40% less students. When an equal number of students joined each school, the ratio of the students in Ivan School to that in Bobby School became 3 : 2. How many students were there in both schools in the end?

	Bobby School	Ivan School	Difference
Before	350		140
Change	+ ?	+ ?
After	3 u	2 u	1 u

Since an equal number of students joined 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 Bobby School and Ivan School at first and in the end the same. 

Difference between the number of students in both schools at first
= 40% x 350
= ⁴⁰₁₀₀ x 350
= 140

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

1 u = 140

Total number of students in both schools in the end
= 3 u + 2 u
= 5 u
= 5 x 140
= 700

Answer(s): 700