Luis School had 590 students and Vincent School had 30% less students. When an equal number of students joined each school, the ratio of the students in Vincent School to that in Luis School became 4 : 3. How many students were there in both schools in the end?

	Luis School	Vincent School	Difference
Before	590		177
Change	+ ?	+ ?
After	4 u	3 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 Luis School and Vincent School at first and in the end the same. 

Difference between the number of students in both schools at first
= 30% x 590
= ³⁰₁₀₀ x 590
= 177

Difference between the number of students in both schools in the end
= 4 u - 3 u
= 1 u

1 u = 177

Total number of students in both schools in the end
= 4 u + 3 u
= 7 u
= 7 x 177
= 1239

Answer(s): 1239