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.
['Q', '4333', '4025', '2833', '9087', 'D', '7773', 'E', '55', 'V', 'f', 'a', 'l', 's', '3197', '9559', 'V', 'f', 'x', 'h']