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: [176.95, -92.841, -33.018, 118.498, 111.391, 220.623, 48.282]

78.555