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.
[[-171, -30, -93, -63, 40, -17], [-14, 81, 21, 14, 36, -55, -99], [-139, -128, -153]]