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: [74.612, 118.316, 223.579, -89.584, -3.216, -91.707, 90.744, 165.764, 232.485, -29.164]

69.183