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: [214.97, 227.824, 175.697, 22.65, 94.011, 21.752, 138.667, 130.376, 83.819]

123.307