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: [61.147, 142.059, 72.591, 148.969, -39.06, 47.712, 74.829, 248.096, 100.913]

95.251