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: [-7.775, 55.997, 216.046]

SOLUTION: 88.089

PROBLEM: [-44.977, 79.906, -20.036]

SOLUTION: 4.964

PROBLEM: [118.783, 191.64, 225.792, 160.903, 209.763, 39.225, 24.607]

SOLUTION:
138.673