The mean age of 10 students is 16 When the teacher is added

The mean age of 10 students is 16. When the teacher is added to the gruop it becomes 19. What is the age of the teacher?

Solution

The mean age of a student is 16. So the sum of ages of the 10 students would be `10xx16 = 160`

Let us say the age of the teacher is x. So with the teacher now we have 11 in the group.

Mean age of gruop = `(160+x)/11`

`19 = (160+x)/11`

`x = 49`

So the teacher\'s age is 49 years.