Question

the mean of 30 students in a class is 14 years . 5 students with mean age 15 years left the class . find the mean age of the remaining student

Answer 1

Mean age of 30 students = 14 years

So, total age of the 30 students = 30*14 = 420 years

Mean age of 5 students that left = 15 years
So, total age of the 5 students = 5*15 = 75 years

Total students remaining = 30 - 5 = 25
Total age of the remaining 25 students = 420 - 75 = 345 years

So, the required mean = 345 / 25 = 13.8 years