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: [198.323, 108.702, 38.704, -8.85, 57.749, 108.604, -20.56, 229.826, -85.953, 177.128]

80.367