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: [-3.07, 84.881, -71.71, 233.544, -77.459, 231.383, 71.796, 189.943, 98.833, -62.965]

69.518