TASK DEFINITION: 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.
PROBLEM: [71.91, 41.513]

SOLUTION: 56.712

PROBLEM: [15.491, 60.283, 240.958, 155.995, 35.585, -55.875, 82.379, 142.503, 95.176, 85.281]

SOLUTION: 85.778

PROBLEM: [117.162, 23.007, 144.696, -81.197, 55.967, -10.966, 220.074, 65.301, 199.508, -4.278]

SOLUTION:
72.927