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: ['2175', '4539', 'L', 'T', 'q', '2407', 'F', 'V', 'b', '9475', '2279', '4469', '6231']
Example Output: 31575

Example Input: ['w', 'V', '3359', '8847', '7551', '2481', 'Y', 'j', 'L', 'G', '7905', 'v', '4141', '2229', 'k', 'H', '3517', '3885', '3665', 'O']
Example Output: 47580

Example Input: ['b', 't', '809', 'h', 'y', 'P', '2803', '9787', '4879', 'X', 'Q']
Example Output:
18278