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.

[231.352, -24.17]
103.591

[21.659, 63.646, -97.361]
-4.019

[219.587, 202.787]

211.187