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: [-75.438, -35.122, 150.678, 152.512, 223.812, 135.057, -84.327, 16.438]

60.451