Question

In a class of 100 students there are 70 boys whose average marks in a subject are 75. If the average marks of the complete class is 72, then what is the average of the girls?

Options

• 73

• 65

• 68

• 74

Answer 1

65

Explanation:

Total student = 100

Total marks of 70 boys = 75 × 70 = 5250

⇒ Total marks of girls = 7200 – 5250 = 1950

Number of girls = 100 – 70 = 30

Average of girls = `1950/30` = 65