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: ['6731', 'f', '4561', '5601', 'i']
Example Output: 16893

Example Input: ['3313', 'H', 'P', '9253', '4131', 'N', '1411', '8877', 'G', '1591', 't']
Example Output:
28576