The average age of a class of 40 students is 12 years. The average age including the teacher becomes 13 years. How old is the teacher?

Open in App

Solution

Average age of 40 students = 12 years

Total age = 40 $\times$ 12 = 480 years

Let the teacher be the 41st member.

Average age now = 13 years

Total age of 41 = 41 $\times$ 13 = 533 years

Age of teacher = 533 - 480 = 53 years

Suggest Corrections

Similar questions

The average age of 29 boys of a class is 17 years . When the age of the class teacher is included , the average age becomes 18 years . Find the age of the class teacher.

Q. The average age of a class of 50 students increases by 1 year if the age of the teacher is included. If the age of the teacher is 61 years, what is the average age of the class excluding the teacher?

Q. The mean age of a class is

16

years. If the class teacher aged

40

years old is also included, the mean age increases to

17

years. The number of students in the class are :

Q. The average age of a teacher and three students is

20

years. If all students are of equal age and the difference between the age of the teacher and that of a student is

20

years, then the age of the teacher is

Join BYJU'S Learning Program

The average age of a class of 40 students is 12 years. The average age including the teacher becomes 13 years. How old is the teacher?

Average age of 40 students = 12 years Total age = 40 × 12 = 480 years Let the teacher be the 41st member. Average age now = 13 years Total age of 41 = 41 × 13 = 533 years Age of teacher = 533 - 480 = 53 years

Average age of 40 students = 12 years

Total age = 40 $\times$ 12 = 480 years

Let the teacher be the 41st member.

Average age now = 13 years

Total age of 41 = 41 $\times$ 13 = 533 years

Age of teacher = 533 - 480 = 53 years