instruction:
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.
question:
['2765', '6767', '7645']
answer:
17177

question:
['9787', '1491', '4411', '5261', 'U', '9787', 'b']
answer:
30737

question:
['K', 'K', 'B', '7651', 'W', '1629']
answer:
9280