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: ['1319', '6105', '1119', 'c', 'p', '7617', '5113', 'a', '5115', '6731', '6693']
Example Output: 39812

Example Input: ['2417', '6671']
Example Output: 9088

Example Input: ['i', '6327', 'g', 'n', 'U', 'V', 'V']
Example Output:
6327