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.
[[-42, -4, -42, -9, -13], [3, 12, 3, 36, -34], [-10, -43, 40, -48], [5, 4], [4, -31]]