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: [-19.756, 27.825, 23.624, 238.804, 122.208, 159.567, 197.245, 12.389, 24.138, 48.017]

83.406