The average age of A and B is 20-years. If C were to replace A, the average would be 19 and if C were to replace B, the averge wouldbe21. What are the age ofA, Band C?

The average of 10 scores is 80. When the highest and the lowest scores are dropped the average is 81. If the highest score is 92, find the lowest score.

A car travels a distance of 120 Km at the rate of 30 Km/h. It covers the nest 150 Km at the rate of 25 km/h and the last 90 Km   of its journey at the speed of 18 Km/h. what is the average speed of the car?

There are two sections A and B of a class, consisting of 36 and 44 students’ respectively. If the average weight of section A is 40kg and that of section B is 35kg, find the average weight of the whole class.

If the average marks of three batches of 55, 60 and 45 students respectively is 50, 55 and 60, then the average marks of all the students is:

In an examinations, a pupil’s average marks were 63 per paper. If he had obtained 20 more marks for his Geography paper and 2 more marks for his History paper, his average per paper would have been 65. How many papers were there in the examination?

The average height of 25 boys is 1.4 m. When 5 boys leave the group, then the average height increase by 0.15 m. What is the average height of the 5 boys who leave ?

The average of 11 numbers is 10.9. If the average of the first six numbers is 10.5 and that of the last six numbers is 11.4, then the middle number is:

The average of 50 numbers is 30. If two numbers, 35 and 40 are discarded, then the average of the remaining numbers is nearly:

A man bought some oranges at Rs. 10 per dozen and bought the same number of oranges at Rs. 8 per dozen. He sold these oranges at Rs. 11 per dozen and gained Rs. 120. The total number oranges bought by him was: