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.

['X', '989', 'U', '9551', '6385', 'Y', '1433', 'J', '1833', '685', 'u']
20876

['5499', '39', 'Q', 'b', 'W', '7155', '2515']
15208

['M', 'p', '2039', 'x', '925', 'H']

2964