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: ['s', 'd', 't', '8235', '2279', '7477', '3029', '4377', '9153', '4309', '2295', '407']
Example Output: 41561

Example Input: ['Q', '2271', '1803', '2363']
Example Output: 6437

Example Input: ['9579', 'E', 'V', 'k', '6631', '4171', 'i', '7047']
Example Output:
27428