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: ['Q', '1767', '5523', 'I', '933', 'h', '2189', 'f', '7795', 'X', 'M', 'G', '1215', 'W', '8619']
Example Output: 28041

Example Input: ['3331', '5791', 'r', 'Q', '2243', '8229']
Example Output: 19594

Example Input: ['6155', 'G', '7449', '5535', 'C', 'I', '1733', 'f', '5929', 'E', 'x', '2491']
Example Output:
29292