A batsman has an average after 16 innings. In 17th innings he scores 85, increasing average by 3. New average?

The average of 6 numbers is 5. The first number is increased by 2, second by 4, third by 8 and so on. The average of new numbers is

The average age of 4 sisters is 7 years. If we add the age of mother, then the average increases by 6 years. Find the age of the mother.

The average age of 30 boys in a class is 15 years. If we include the age of two teachers the average age increases by 1. Find the sum of ages of the two teachers.

Average age of a group of 30 boys is 16 years. A boy of age 19 leaves the group and a new boy joins the group. If the new average age of the group is 15.8 years, find the age of the new boy.

Ramesh scores in five math tests are 89, 75, 78, 84 and 83. What does he need to score in the next test for his final average in all the tests to be at least 82?