Question

The average age of an adult class is 40 yrs.12new students with an average age of 32 join the class thereby decreasing the average of the class by 4.find the original strength of the class

Answer 1

let 'n' be original class strength in adult class.

Avg of class after adding 32 students became 36=(12(32)+40(n))/(12+n).

On simplifying it we get value uf n as 12 which is = original class strength