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: ['2417', '6671']
Example Output: 9088

Example Input: ['S', 'W', '2171', '6405', 'h', 'C', '1597', '7109', 'Q', 'p', '2747', 't', 'J', 'q', '1883', 'v', 'O']
Example Output: 21912

Example Input: ['5721', '2165', 'P', 'n', '3925', '6069', 'B', 'Z', 'W', 'x', 'F', '4189', 'x', '3621', 'G', 'D']
Example Output:
25690