The average age of a child in a class of 35 is 11. The average age, including the teacher is 12. How old is the teacher?

Explanation

Ans: The average of age of a child in `mathrm(a)`. class of `35=11`
Total.age of 35 children=11 xx 35=385

The average age, including the teacher=12

Total age of 35 children and teacher=12 xx 36=432

Age of the teacher `=432-385=47` Another.method The average age of a child in aclass of 35 =11

Average age of 36 , including the teacher=12

If we say the average of 36 , including the teacher is 12 , the age of each one is 12 . But there is no change in the age of the children, the teacher.s age is only change. So, 12, is added to 35 . Thát is, age of the teacher, `=35+12=47`