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: [-74.006, 221.05, 183.353, 203.998, -55.991, 119.453, 155.004, 151.412]

113.034