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: [229.556, 154.49, 249.611, -84.337, -98.549, 130.576, 207.072, 118.09, -43.198, 74.119]

93.743