Question

the average age of a class of 39 students is 15 years. if the age of teacher be included, then the average increases by 3 months .find the age of the teacher​

Answer 1

Answer:

The age of teacher is 25 years.

Step-by-step explanation:

Let the total sum of ages of all students be x.

15 years in months = 15 × 12 = 180 months

So, x/39 = 180 months

x = 7020

Let the teachers age be y.

So according to given condition we have,

(x + y)/40 = 180 + 3

7020 + y = 183 × 40

y = 7320 - 7020

y = 300 months

y = 300/12

y = 25 years