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: [15.381, -32.835, 231.553, 185.532, 69.076, 159.671, 209.149, 51.605]

111.142