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

Example Input: [169.131, -79.809, 119.898, 174.146, -1.167, 89.734, 155.318, -26.905, 182.476, 164.085]
Example Output: 94.691

Example Input: [-79.521, 169.962, 120.036, -71.612, -53.261, -90.734, -35.559, 140.419, 25.016]
Example Output:
13.861