The table shows the children in a class, sorted according to the marks they got for a math test.

Calculate the average marks of the class.

The weight of 6 players in a volley ball team are all different and the average weight is 60 kilograms.

i) Prove that the team has at least one player weighing more than 60 kilograms.

ii) Prove that the team has at least one player weighing less than 60 kilograms.

Find two sets of 6 numbers with average 60, satisfying each of the conditions below:

i) 4 of the numbers are less than 60 and 2 of them greater than 60.

ii) 4 of the numbers are greater than 60 and 2 of them less than 60.

The table below shows the days in a month sorted according to the amount of rainfall in a locality.

What is the average rainfall per day during this month?

The details of rubber sheets a farmer got during a month are given below.

i) How many kilograms of rubber did he get a day on average in this month?

ii) The price of rubber is 120 rupees per kilogram. What is his average income per day this month from selling rubber?