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: ['5947', 'n', '9431', '7629', '7643', 'N', '141', '2353', 'l', 'F', '9665', '9489', 'X', '4905', 'H', 'L', '985']
Example Output: 58188

Example Input: ['7187', '5651', 'd', '4869', 'q', '2375', '3547']
Example Output: 23629

Example Input: ['4827', '3771', '31', 'K', 'N', '1125', '4341']
Example Output:
14095