In this task, you will be given a list of numbers. The goal is to divide all the numbers in the list by a constant such that the sum of the resulting list is 1. The output should be rounded to 3 decimals.
[-74.662, 217.357, 243.77, 167.096, -89.253, 20.36, 128.136, 127.044, 239.12, -69.956]