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: [-84.97, 158.563, 27.96, 41.849, -2.101, 35.984, 57.271, 148.387]

47.868