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: ['191', 'R', 'Q', '7809', '4851', 'b', 'e', 'H', 'E', 'I', 'r', 'A', 'g', 'e', 'g', 'I', 'j', 'f', '7287']
Example Output: 20138

Example Input: ['L', 'i', '9225', 'w', '5365', '8077', '2733', 'W', '8493', 'B']
Example Output: 33893

Example Input: ['6195', '1775', 'y', '8459', 'r', 'a', 'U', 'p']
Example Output:
16429