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.

[-55.198, 36.097, 190.132]
57.01

[-42.956, 89.597, -60.477, 101.972, 77.479]
33.123

[-84.522, -84.904, 107.97, 176.476, 221.07, 52.302, 223.497, 64.707, 111.483]

87.564

