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.

[153.482, 150.917]
152.2

[-77.226, 44.49]
-16.368

[73.813, -73.579, 234.134, -34.366]

50.0