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: [-69.822, 145.439, 182.399, 209.852, 92.527, 90.773, -42.227, 94.817, 118.024, 229.224]

105.101