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.
['W', 'V', 'I', '427', '645', '8313', '6179', 'J', '3541', 'q', '9547', 'a', 'j', '4269', '5011', 'z', '2149', '5679', 'x', 'V']