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: ['7361', '6913', '3605', '2081', '7619']
Example Output: 27579

Example Input: ['Q', '1669']
Example Output: 1669

Example Input: ['M', '8305', 'x', 'V', 'b', '4617', '2849', '563', 'Z', '4745', '8463', 'n', 'G', 'o', 'w', 'H', '243']
Example Output:
29785