Answer:
First, we need to figure out the total amount of students:
+ 10 students(ten students leave)
+ 15 students(15 students left)
10 + 15
= 25 students.
x = will represent the total amount of students in each group, so:-
5 groups per x students.
5x = 25(total students before alteration)
÷5 ÷5
x = 5, there are 5 students in each group.