Arithmetic Averages Mock Tests

The average of 8 numbers is 15. If the average of the first 5 numbers is 12, what is the average of the remaining 3 numbers?

The average (arithmetic mean) of 10 numbers is 50. If one of the numbers is increased by 30, what is the new average?

The average of 5 numbers is 24. If one number is removed, the average of the remaining 4 numbers is 20. What is the removed number?

What is the average of the numbers 3, 5, 7, 9, and 11?

A data set has 20 values with mean 15. If two values of 10 and 20 are added, what is the new mean?

The average of 5 numbers is 20. If one number is excluded, the average becomes 18. What is the excluded number?

If the arithmetic mean of five consecutive integers is 21, what is the largest of the five integers?

The average of 8 numbers is 15. If one of the numbers is replaced by a number that is 10 more than the original, what is the new average?