Exercises

The mean weight of players on a football team is 81 Kg. The weights are:

88, 72, 60, 60, 92, 76, 76, 100, 88, 72, 92, 88, 68, 64, 76, 100, 72, 80, 100, ? , where one number is missing. Find it.
The misssing value is Kg.