Question

There are 30 boys and 40 girls in a class. If the average age of boys is 10 yr and the average age of girls is 8 yr, then the average age of the whole class is

विकल्प

• 8 year

• 8.86 year

• 8.2 year

• 9 year

Answer 1

8.86 year

Explanation:

Average of 30 boys and 40 girls

`=(30xx10+40xx8)/(30+40)=(300+320)/70`

= 8.86  yr approx