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 Q]: [-51.625, 100.25, -75.262, -53.896]
[EX A]: -20.133

[EX Q]: [246.278, 103.84, 214.867, -73.466, 230.048, -72.322, 172.891, 212.306, -78.335, 122.406]
[EX A]: 107.851

[EX Q]: [123.607, 44.731, 186.89, -71.538, -73.171, -73.099, 60.136]
[EX A]:
28.222