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: [66.037, 30.958, 124.853]
Example Output: 73.949

Example Input: [233.84, -38.337, 10.341, 195.901, 68.586, 214.429, 213.823, 88.799]
Example Output: 123.423

Example Input: [36.398, -99.571, -52.167, 120.272, 187.047, 150.904, -73.368, 76.442]
Example Output:
43.245