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: [85.925, 218.341, -55.232, 136.11, 243.387, 98.158, 183.742, 85.875, 124.291, -95.213]
Example Output: 102.538

Example Input: [-32.03, 84.065, 91.512, 156.512, 78.808, 165.396, 176.764, 116.6]
Example Output: 104.703

Example Input: [230.416, -57.729, 214.095, 137.62, 196.636, 137.956, 199.628, -57.559, 16.386, 186.284]
Example Output:
120.373