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: [85.011, -20.439, 195.195, 114.286]
Example Output: 93.513

Example Input: [15.748, -13.369, -79.943, -2.78, 169.174, 101.44, -84.923, 189.589, 83.541, -37.629]
Example Output: 34.085

Example Input: [60.02, -66.628, -95.571, 114.26, 109.577, 141.08, 154.303, 228.454, 46.856, 7.365]
Example Output:
69.972