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: [239.96, 143.808, 223.874, 249.699, 207.385, 225.049, 179.984, 110.664, 170.793]

194.58