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: [105.806, 71.753, 57.545, 229.364, -49.498, 167.773, -31.267, 50.402, 64.235]

74.013