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

Example Input: ['I', '1941', '2423', '3381', 'J', '6589', 'h', 'D']
Example Output: 14334

Example Input: ['3417', 'l', '4305', 'z', '85', 'j']
Example Output:
7807