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: [-45.201, 161.25, -67.093, 105.259, 110.499, 224.516, -55.166, 11.51]
Example Output: 55.697

Example Input: [216.087, 41.07, 213.683, 53.822, 31.214]
Example Output: 111.175

Example Input: [-76.343, 242.615, -57.476, 162.015, -72.399]
Example Output:
39.682