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: ['1671', 'H', '9271']
Example Output: 10942

Example Input: ['9211', '1889', '7371', '9649', 'b', 'y', 'q', 'a', 'i', '1137', '3291', '8625']
Example Output: 41173

Example Input: ['2559', '721', '6765', 'p', '2863', 'Y', 'O', '1977', '8973', '4345', '3483']
Example Output:
31686