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.

[-6.992, -36.177, -95.203, 87.142]
-12.808

[192.74, 78.623, -5.937, 144.535]
102.49

[155.527, 230.296, 22.062, 210.181, 42.788, -92.124]
94.788