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: ['887', '8133', 'X', '2253', '8461', 'I', '5425', 'Z', 'z', 'r']
Example Output: 25159

Example Input: ['D', 'P', '9951', '2897', 'V', 'C', 'B', 'H', 'c', 'h', '2843', 'a']
Example Output: 15691

Example Input: ['k', '8735', '3445', 'T', 't', '4799', '9365', '3943', 'C', '1599', '8421', '1193', 'L', 'A', '5507', '9517', '5645', 'b']
Example Output:
62169