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: [158.197, 125.394, 249.532, 145.426, -38.449, -55.294, 24.725, 78.56, 180.519]

96.512