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: [233.84, -38.337, 10.341, 195.901, 68.586, 214.429, 213.823, 88.799]
Example Output: 123.423

Example Input: [145.697, -40.957, -46.926, -55.065, 177.211, 204.811, -94.192, -47.466]
Example Output: 30.389

Example Input: [-94.662, 205.239, 110.714, 130.064]
Example Output:
87.839