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: [115.312, 165.47, 247.989, -43.103, 132.924, 124.421, 175.521, 7.047, -7.973, 88.174]

100.578