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: [[42, -43], [-19, 31], [-47, -33], [46, 48, 31]]

[-1806, -589, 1551, 68448]