The arithmetic mean of the following data is .

23, 17,20,19,21

A number when divided by 119, leaves a remainder of 19. If it is divided by 17, it will leave a remainder of: 

The sum of all natural numbers between 100 and 200. Which are multiple of 3 will be: 

Two numbers are respectively 30% and 40% less than a third number. What percent is the first number of the second?

Two numbers are such that their difference, their sum and their product is in the ratio of 1: 7: 24. The product of numbers is

Divide 50 into two parts so that the sum of their reciprocals is   $${1\over 12} $$

What should be added at least in 1140 so that it becomes a perfect square?

If the sum of first three natural numbers from a group of six consecutive natural numbers is 36, then the sum of last three natural numbers will be?