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.

Example Input: ['4811', 'Q', '2289', 'N', 'I', '7681', 'z', '8179', '3359', '5299', 'R', 'z', '8697', '5781', '4803', '2715', '6511', '1371']
Example Output: 61496

Example Input: ['9403', '2607', 'G', '7901', 'K', '7967', 'a', 'n', '1967', 'x', 'g', '1081']
Example Output: 30926

Example Input: ['5259', 'v', 'L', '823', 'o', 'g', '3713', 'Z', 'v', 'a', '7229', '6691', 'k', '5975', 'O', 'v', 'v', '477', '2625', 'F']
Example Output:
32792