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.

[-66.735, 23.822, -34.5, 118.327, 242.333]
56.649

[199.153, 182.13, -7.832, -60.259]
78.298

[-9.435, 88.384, -52.794]

8.718