In this task you will be given a list of lists, of numbers. For every inner list, you should multiply every number in that list and put the results in your answer. The output should be a list of numbers with the same length as the number of the lists in the input list.
[[-20, -18, -29, -23], [-34, -27, -32, 48, 12], [-2, 37, 50], [5, -8, 20]]