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: [-75.179, 16.007, 168.16, -50.911, -93.426, 16.977, 148.591, 46.605, -61.756]

12.785