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: [47.085, -20.927, -10.587, 232.022, 155.57, 226.624, 128.252, 116.545, -92.461]

86.903