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: ['V', '2633', '3269', 'r', 'Q', '3517', '2571', 'G', '4105', 'm', 'z', 'B', 'A']
Example Output: 16095

Example Input: ['3497', '761', '6157', 'J', 'n', '139', '9895', '2939', 'K', 'I', '2161', 'c', 'a', '485', '7959', 'i', '4753', '3305', 'G', '3475']
Example Output: 45526

Example Input: ['5715', '155', 'I']
Example Output:
5870