The number of students in 3 classes is in the ratio 2 : 3 : 4. If 10 students are increased in each class this ratio changes to 8 : 11 : 14. The total number of students in the three classes in the beginning was-

Question: The number of students in 3 classes is in the ratio 2 : 3 : 4. If 10 students are increased in each class this ratio changes to 8 : 11 : 14. The total number of students in the three classes in the beginning was-

Solution:
Let the number of students in the classes be 2x, 3x and 4x respectively;
Total students = 2x + 3x + 4x = 9x
According to the question,
(2x+10) : (3x+10) = 8 : 11
or, 11(2x+10) = 8(3x+10)
or, 22x + 110 = 24x + 80
or, 2x = 30
or, x = 15

Hence,
Original number of students,
9x = 9×15 = 135