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.

[207.165, 246.399, 44.821, -21.671]
119.178

[-72.554, 9.809, 27.09, 190.698]
38.761

[228.646, -26.004, 175.415, 53.329, 5.579, 89.641, 19.887, 103.431, -78.426]

63.5