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: [-47.309, -46.076, 191.14, -6.032, 4.858]
Example Output: 19.316

Example Input: [187.54, -56.697, 55.301, 235.071, 176.682, 103.554, -35.29, 84.215]
Example Output: 93.797

Example Input: [-36.393, 96.684]
Example Output:
30.146