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.
[[19, -1, -19, 11, 48], [15, 45, 28, 49], [-18, -42, 10, 2], [6, 17], [43, 36, -31, 13]]