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: ['R', '9751', '4367', 'l', 'N', '5125', '8751', '7507', 'y', 'K', '6127']
Example Output: 41628

Example Input: ['6833', 'R', '7323', 'd', '3487', '8777', '9053', 'y', 'i', 'O', '467', 'b', '5969', 'D', 'B', 'r', '3073', 'i', 't', 'd']
Example Output: 44982

Example Input: ['h', 'X', '6705']
Example Output:
6705