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: [243.119, 198.975, 44.828, 192.078, 66.175, 169.375, 220.423, 45.768, 20.289, -56.022]

114.501