Question

In a class of 25 students

Answer 1

If the mean height of 15 girls is 1.65m, the sum of the girls’ heights is 15×1.65=24.75m.

If the mean height of 10 boys is x metres, the sum of the boys’ heights is 10x m.

The sum of all 25 srudents’ heights is 25×1.682=42.05m.

Therefore, 24.75+10x=42.05, x=(42.05-24.75)/10=1.73m, the mean height of the boys.