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: [65.727, 216.759, 101.145, 91.028]
Example Output: 118.665

Example Input: [233.742, -71.075]
Example Output: 81.333

Example Input: [-50.219, 16.731]
Example Output:
-16.744