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: [-87.411, -18.524, 168.788, 112.685, 47.151, -70.348, 128.549, 9.845, -1.18, -53.661]

23.589