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: [126.021, 179.671, -47.468, 176.927, 243.29, 157.208, 140.121, -36.094, -26.018, 14.231]

92.789