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.

Ex Input:
[-86.423, 157.154, 69.563, -67.516, 147.66, 216.018, 213.404]

Ex Output:
92.837

Ex Input:
[108.26, -20.681, 127.479, -29.352]

Ex Output:
46.426

Ex Input:
[-64.114, 105.827, -30.412, 155.456, -16.765, 244.443]

Ex Output:
65.739