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: ['1319', '6105', '1119', 'c', 'p', '7617', '5113', 'a', '5115', '6731', '6693']
Example Output: 39812

Example Input: ['8529', '2657', '1599', 'b', '8187', '7005', '7481']
Example Output: 35458

Example Input: ['4333', 'a', 'u', '1415', '3899', 'D', 'J', '8083', '4829', 'r', 'G', '691']
Example Output:
23250