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: [207.778, -78.48, 106.025, 89.5, -66.261, 3.733, 236.586, 234.142]

91.628