The average age of 25 girls in a class is 11.2 years and that of the remaining 15 girls is 10 years. Find the average age of all the girls in the class.

10.75 years 11.35 years 10.45 years 11.05 years

10.75 years

Sum of ages of all girls = 25x 11.2 + 15 x10 = 430 Avg. age = \(\frac{430}{40}\) = 10.75 years