Bobby School had 580 students and Luis School had 10% more students. When an equal number of students left each school, the ratio of the students in Luis School to that in Bobby School became 2 : 1. How many students were there in both schools in the end?

	Bobby School	Luis School	Difference
Before	580		58
Change	- ?	- ?
After	2 u	1 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 Bobby School and Luis School at first and in the end the same. 

Difference between the number of students in both schools at first
= 10% x 580
= ¹⁰₁₀₀ x 580
= 58

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

1 u = 58

Total number of students in both schools in the end
= 2 u + 1 u
= 3 u
= 3 x 58
= 174

Answer(s): 174