Question

A science exam has been conducted by the school between section A, section B, and section C of class 9^th students. The average marks of section A is 65, section B is 71, and section C is 68. If all sections were an equal number of students then find overall average marks of class 9^th.
1. 58
2. 55
3. 68
4. 65

Answer 1

Correct Answer - Option 3 : 68

Given:

Average of marks of three classes are 65, 71, and 68

Concept used:

Average = (Total of all the variables/ No. of variables)

Calculation:

Total marks of three classes = 65 + 71 + 68

⇒ 204

Average marks of three classes taken as together = 204/3

⇒ 68

∴ Overall average marks of class 9 is 68