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: [10.724, -65.993, 107.56, 154.38, 117.135, 114.495, 11.544]

64.264