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: [38.24, 196.576, -84.173, -45.001, 1.607, 170.177, 234.811, -60.183, -91.513]
Example Output: 40.06

Example Input: [4.435, 100.482, 125.267, -76.982, 9.994, 192.069, 54.099, -40.749]
Example Output: 46.077

Example Input: [244.419, 64.966, -38.225, 28.882, 49.623, 90.963, 49.927]
Example Output:
70.079