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.
[[29, 25, -39], [-6, 28], [-3, -4, -42], [-29, 22, 23, -9], [20, 50]]