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.
['4933', 'Z', '467', '1255', 'W', 'O', '4943', 's', '599', '8495', 'E', 'x', 'Y', 'C', '9193', '4155', 'n', 'b']