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.

[71.91, 41.513]
56.712

[-98.163, -66.763, 149.544, -89.893, -10.155]
-23.086

[7.487, 96.329, 178.464, 210.823, 121.521, 229.021, -66.53, -79.514]

87.2