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: [228.441, 187.318, 149.618, 139.523, 206.938, -84.668, 180.046, 118.108]

140.666