The average of seven numbers is 18. Accordingly, if one of them If the number is 17 and it is changed to 31, then the average How much will it be?

The average of 2 numbers is M if one number & N, then the other number is _____

The average of 8 numbers is 14. The average of 6 of these numbers is 16. What is the average of the remaining two numbers?

The average (arithemetic mean) of a set of seven numbers is 81. If one of the numbers is discarded, the average of the remaining number is 78. What is the value of the number that was discarded?

The average of 17 numbersis 29. The averageoffirst 9 numbers is 31 and the averageof the last 9 numbers is 27. If 9th number is excluded, then what is the average of the remaining numbers?