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.

[-1.31, 169.522, -26.172, 111.289]
63.332

[183.332, -51.581, -15.684, 140.965, 37.376, 37.734, 71.356]
57.643

[169.83, -50.376, -2.571, 216.038, 98.437]

86.272