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: [-85.019, 112.689, -26.082, 206.652, 174.103, 30.316, 139.997, 248.12, 117.027]

101.978