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: ['6255', '8457', 'V', 'z', '4405', 'X', '9267', '5329', 'I']
Example Output: 33713

Example Input: ['R', '3361', 'c', 'S', 'g', '3829', '7347', '6633', 'e', '9227']
Example Output: 30397

Example Input: ['1861', 'L', 's', 'H', 'u', 'A', '2217', 'V', '1937', 'H', '8397', 'c']
Example Output:
14412