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.

['7411', 'Y', 'x', 'l', '4119', '7241']
18771

['c', '7415', '6253', '4477', 't', '9449', '7733', '2325', 'Z', '5413', 'q', 'm', 'R', '8619', '7289', '857', '7273', '7425']
74528

['8459', '2207', 'i', 'C', 'i', 'u', '9359', 'n', '2027', 'b', 'b', 'E', '531', '1879', '6455', '3501', '3155', 'U']

37573