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.
Q: ['Y', '4975', 'N', 'P', 'B', 'c', '261', 'i', '3155', '1177', 'H', 'g', '9775']
A:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
19343