In this task you will be given a list of numbers and you need to find the mean (average) of that list. The mean of a list can be found by summing every number in the list then dividing the result by the size of that list. The output should be rounded to 3 decimal places.

[14.818, 98.871, -79.033]
11.552

[211.292, 92.275, 128.423, 242.327, -54.053, 89.501, 64.784]
110.65

[17.093, 20.049, 20.223, -5.753, -15.881, -78.606]

-7.146