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: [[49, -9, -12, 50], [9, 13, 8, -2, -42]]

[264600, 78624]