TASK DEFINITION: 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.
PROBLEM: ['191', 'R', 'Q', '7809', '4851', 'b', 'e', 'H', 'E', 'I', 'r', 'A', 'g', 'e', 'g', 'I', 'j', 'f', '7287']

SOLUTION: 20138

PROBLEM: ['7293', '2619', '2459', '3829', 'J', 'c', 'a', 'a', '311', 'x', 'r', '6123', '2847', '4809']

SOLUTION: 30290

PROBLEM: ['5327', '6543', '6247', 'w', 'Z', '5171']

SOLUTION:
23288