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: ['a', 'j', 'v', '619', 't', 'a', '5777', 'x', 'R', 'P', '8897', 'j']
Example Output: 15293

Example Input: ['6849', 'I', 'p', 's', 'L', '4757', 'j', 'x', 'm', 'P', '5237', '1105', '9015', '9279', 'Q']
Example Output: 36242

Example Input: ['W', '5553', '695', 'V', 'm', '5189', 'Q', 'a', 'y', '2977', 'I', '779', 'V', '335', 'D']
Example Output:
15528