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.
[[-138, 90, -42, -129], [-177, -81, -41, -121, 27, -120], [-129, -136, 1, -102, -142, -120]]