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: [15.748, -13.369, -79.943, -2.78, 169.174, 101.44, -84.923, 189.589, 83.541, -37.629]

34.085