Answer:
Number of students in each van = 18
Number of students in each bus = 53
Explanation:
Given: The senior class at High School A rented and filled 2 vans and 7 buses with 407 students. 
High School B rented and filled 1 van and 7 buses with 389 students.
Also, every van and the van had the same number of students in it.
Solution:
Let x denotes number of students in each van and y denotes number of students in each bus.
According to the given information,

From (ii), put 
 in (i)
 in (i)


Put 
 in
 in 


Number of students in each van = 18
Number of students in each bus = 53