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: [26.857, -69.553, -37.942]

SOLUTION: -26.879

PROBLEM: [38.343, 177.478, 120.174, -74.923, 98.159]

SOLUTION: 71.846

PROBLEM: [-29.848, 95.809, 223.477, 112.976]

SOLUTION:
100.604