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.

[93.405, -31.061]
31.172

[53.391, 118.782, 102.742]
91.638

[-73.23, 41.467, 183.516, 85.92, 21.649, 218.253, 15.001]

70.368