Find the mean (average) of a list of numbers in an array.
To find the mean (average) of a set of numbers add all of the numbers together and divide by the number of values in the list.
For an example list of 1, 3, 5, 7
1. Add all of the numbers
1+3+5+7 = 16
2. Divide by the number of values in the list. In this example there are 4 numbers in the list.
16/4 = 4
3. The mean (or average) of this list is 4