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.
['8395', '9399', 'd', 'M', 'i', '6559', '27', '2155', '4263', '6693', 'o', '139', '9835', '8551', '1425', 'd', 'i', '7011']