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.
['8343', 'L', '2931', '6585', 'i', 'b', 'c', '2395', 'D', '9215', 'c', '3533', 'Y', '1475', 'A', 'b', 'g', '3083']