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.

Ex Input:
[-51.625, 100.25, -75.262, -53.896]

Ex Output:
-20.133


Ex Input:
[-57.838, -63.616, 49.646, -45.262, 73.1, -82.399, 47.168]

Ex Output:
-11.314


Ex Input:
[105.182, 44.508, 158.846, -64.727, -21.832, -97.733]

Ex Output:

20.707