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: [207.434, -54.286, 205.305, 84.324, -62.931, -78.806, -22.959, -67.369, -55.279, -98.626]

5.681