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: [142.918, 73.538, -21.54, -52.028, 103.72, 85.296, -39.189, 70.144, 118.987, 142.673]

62.452