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: [182.66, 166.228, 127.473, 61.425, 25.582, 21.339, -47.206, 149.029, 128.768]

90.589