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: ['191', 'R', 'Q', '7809', '4851', 'b', 'e', 'H', 'E', 'I', 'r', 'A', 'g', 'e', 'g', 'I', 'j', 'f', '7287']
Example Output: 20138

Example Input: ['7187', '5651', 'd', '4869', 'q', '2375', '3547']
Example Output: 23629

Example Input: ['B', 't', 'N', 'Z', 'q', '4121', 'N', 't', 'p', 'W', '2669', 't', '6507', '4869', '6529', '5841', '3669', '1787', 'A', '7291']
Example Output:
43283