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:
['2787', '6085', '6989']
answer:
15861


question:
['r', '3537', 'T', '3611', 'k', '4983', 'h', '4317', '8727', 'E', '6471', '8465', 'f', '5429', 'T', '2169', '2171', 'P', '6941', 'D']
answer:
56821


question:
['6269', 'L', '1639', 'y', 'N', 'a', '4683', 'E', '1315']
answer:

13906