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: ['d', '7305', '8903', 'b', '7687', '6393', '6939']
Example Output: 37227

Example Input: ['c', '7415', '6253', '4477', 't', '9449', '7733', '2325', 'Z', '5413', 'q', 'm', 'R', '8619', '7289', '857', '7273', '7425']
Example Output: 74528

Example Input: ['w', 'd', '2395', 'B', 'M', '9905', 'l', '8253', '9913']
Example Output:
30466