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.

Example Input: [232.39, 28.124, 179.446, 228.788, 90.985, 60.823, 92.908]
Example Output: 130.495

Example Input: [127.703, -82.203, 53.438]
Example Output: 32.979

Example Input: [145.813, 207.226, 199.292]
Example Output:
184.11