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: ['2683', '4431']
Example Output: 7114

Example Input: ['z', '447', '9781', 'R', '6083', 'u', '9229', 'Z', 'F', '2437', '9677', 'n', 'G', '6763', '5883', 'B', '9563', '4575']
Example Output: 64438

Example Input: ['g', '7561', 'A', '8667', 'X', 'l']
Example Output:
16228