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: [195.019, 144.893, 32.821, -21.855, 136.755]
Example Output: 97.527

Example Input: [41.081, 166.314, -14.556, -84.648, -8.286]
Example Output: 19.981

Example Input: [127.967, 42.005, 168.717, 172.051, -22.167]
Example Output:
97.715