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: [-30.053, -38.855, 221.016, -4.563, -42.383, 194.358, 174.21, 99.965, 224.828, 246.88]

104.54