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: [87.02, -25.654, -67.979, 52.368, 20.078, 160.939, 4.162, 205.092, -57.092, -68.35]
Example Output: 31.058

Example Input: [113.238, 247.072, -31.448, -33.563, 74.519, 67.841]
Example Output: 72.943

Example Input: [233.835, 33.626, 110.976, 132.274, 152.818]
Example Output:
132.706