Question

The mean of 100 children of a nursery school is 7 years. Among these 100

children 40 are boys and the rest are girls. If the mean age of boys is 8

years, find the mean age of girls.​

Answer 1

Answer:

= total age of all students = 100×7 = 700

there are 40 boys

= total age of all boys = 40×8

= 320

= total age of all girls = 700-320

= 380

mean age of girls = 380/60

= 6.33333333 years