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: [-94.827, -4.806, 33.138, 11.562, -68.261]
Example Output: -24.639

Example Input: [4.435, 100.482, 125.267, -76.982, 9.994, 192.069, 54.099, -40.749]
Example Output: 46.077

Example Input: [221.679, 16.334, 157.622, 118.18, 168.849, 157.974, 37.636, 249.085, -10.276, 70.5]
Example Output:
118.758