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: [16.863, 133.667, 174.854, -1.397, -96.701, 182.413, -68.222]

48.782