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: [-70.607, 41.066, 49.614, 153.242, 247.484, 218.658, -64.966, 210.487, 218.364, -76.468]

92.687