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: ['K', 'O', 'p', '1669', '8647', '3417', 'a', '8903', 'V', 'E', 'l', 'a', '5177', 'J', '6559', '5377', 'X', '9427']
Example Output: 49176

Example Input: ['k', '6555', 'L', '7549', 'W', 'y', 'y', '8817', 'J', 't', 'X', 'M', 'N', 'G', '7441', '283']
Example Output: 30645

Example Input: ['N', '7065', 'T', '5817']
Example Output:
12882