Question

The ratio of students of three classes is 2:3:4. If 12 students are increased in each classes then their ratio turns into 13:18:23. What was the total number of students in all the three classes originally ?

Answer 1

Let the number of students in the classes be

2x

3x and

4x

Total students = 2x+3x+4x = 9x.

A.T.Q

(2x+12)/(3x+12) = 8/11

24x+96 = 22x+132

2x = 132-96

x = 36/2

x = 18

Hence, Original number of students,

9x = 9*18 = 162.

Answer 2

Please see the attachment