Mean

The mean of a set of numbers is their average.
You find the average of a set of numbers by adding them up and dividing by the number of numbers you have.
So, the mean of {3, 4, 6, 9, 3} is:


            3 + 4 + 6 + 9 + 3      25
            -----------------  =   --  = 5
                   5                5

For a more in-depth discussion of mean and other statistics, see the Statistics notes.