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.

['6001', '6423', '5591', '8721', 't', 'x', '3723', 'E', 'F', '7353', 'b']
37812

['h', '2335', '2669', '6035', '9901', '7721', 's', '6181', 'C', 'l', 'x', '8275', '1103', 'S', '6447']
50667

['4831', 'j', 'K', 'd', '2817', 'a', '61', '8909', 'A', '3537', 'f', 'x']

20155