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.

['E', 'X', 'C', 'v', '2803', 'g', 'b', '763']
3566

['D', 'G', '9895', '143', '37', 'S', '1539', 'x', 'a', 'x', 'B', 'i', '9719', '839']
22172

['8939', 'D', '5135', '7459', '4803', 'o', '6171', '8819', 'k']
41326