Definition: 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.
Input: [[-31, -29, -48, 16, 2], [-1, -40, 13, 49, 2], [-28, 4, -29, -15], [50, -21, 8, 29]]

[-1380864, 50960, -48720, -243600]