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: [78.523, 239.098, 9.698, 69.94]

SOLUTION: 99.315

PROBLEM: [98.834, 143.231, 35.995, -64.696]

SOLUTION: 53.341

PROBLEM: [61.915, 139.958, 138.08, 174.984]

SOLUTION:
128.734