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: [-52.581, 5.629, 120.345, -3.244, 229.948, -20.784, -21.229, 90.361, 11.368, -68.349]

29.146