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: [38.198, 26.324, 56.332, -32.007, 162.261, 77.154, -70.885, 47.784, 120.58]

47.305