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: [113.25, 20.985, 192.351, 206.308, 95.11, 92.787, -16.318, 172.167]

109.58