In this task, you are given an input list A. You need to find all the elements of the list that are numbers and calculate their sum.
['8547', 'H', '7897', 'S', '2009', '5115', '1931', 'J', 'B', '4465', 'h', '5693', '1857', '5485', '8237', '6757', '9241', 'J']