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: [223.847, 115.483, 148.407, -44.824, 99.251, 36.833, -45.949]

76.15