Definition: 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.
Input: [-30.813, 30.325, 17.44, 231.059, 105.014, 210.93, 113.827, 159.848]

104.704