Out of 20 boys, 6 are each of 1 m 15 cm height, 8 are of 1 m 10 cm and rest of 1 m 12 cm. The average height of all of them is

Average weight of 10 persons is 40 kg. A new person join the group and average weight of 11 persons becomes 42 kg. What will be the weight of new person?

Answer the following questions

There are three numbers in such a way that the average of the first and second numbers is 68 more than the average of the second and third number. Find the difference between first and the third number.

The average salary of the entire staff in an office is Rs 3200 per month. The average salary of officers is Rs 6800 and that of non-officers is Rs 2000. If the number of officers is 5, then find the number of non-officers in the office.

The average of 11 numbers is 7. If each number is doubled, what will be the new average of the numbers?

A factory buys 7 machines. 2 Machine A, 2 Machine B and rest Machine C. Prices of the machines are Rs 95000, Rs 75000 and Rs 43000 respectively. Calculate the average cost of these machines?

The average of the largest and smallest 3 digit numbers formed by 0, 2 and 4 would be 

The average of 30 numbers is 40 and that of the other 40 numbers is 30. The average of all the numbers is-