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.
['2247', 'e', '293', 'S', 'E', 's', '6465', 'S', 't', 'g', '9303', '497', '8235', '8015', 'b', 'i', 'Y', 'C', 'M']