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: ['8109', '6811', 'f', 'l', '5869', 'm', '4657', 'y', 'P', '7983', 'o', 's', 'i', 'm', '2141', '4497']
Example Output: 40067

Example Input: ['2895', '8095', 'y', '1927', '4827']
Example Output: 17744

Example Input: ['4379', 'Y', 'f', 'v', 'c', '2133', '2049', 'O', 'N', 'Q', 'd', '8073', 's', '3875']
Example Output:
20509