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: ['m', '4645', '711', 'l', '5085', '8989', '2387', 'n', 'V', '1613', '4011', '3261', 'p', 'X', '349', 'e']
Example Output: 31051

Example Input: ['I', '7815']
Example Output: 7815

Example Input: ['6553', '159', '6033', 'i', 'z', 't', 'H']
Example Output:
12745