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.

Example Input: [47.595, -7.171, 4.333, 160.025, 152.275, 90.23, 128.643, 145.181]
Example Output: 90.139

Example Input: [96.706, 239.918, 73.299, 68.184, 233.512, -76.407]
Example Output: 105.869

Example Input: [195.257, 122.676, 96.331, 163.695]
Example Output:
144.49