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.
Input: [10.369, 67.912, -40.667, 134.716, -66.642, 73.952, 208.18, -10.322, -15.676, 84.776]

44.66