In this task, you are given a list. This list contains many lists of integers. The list is several items written within a []. Your task is to find the maximum number among the members of each inner list. The output should be a list comprised of the maximums with the same order as the internal lists.
[[-117, -110, 36, 18], [-15, 40, -140], [-33, 79, 8, 42, -4, 84]]