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: ['4607', 'T', 'a', '6077', 'c', '4761']
Example Output: 15445

Example Input: ['4389', '8535', 'D', '6063', 'z', 'r', 'w', '5725', '291', 'a', '9059', '569', '2943', 'W']
Example Output: 37574

Example Input: ['N', '333', 'G', 'x', '3175', '5711', 'W', 't']
Example Output:
9219