Multiplying 9s

Any multiple of nine will have digits that add up to nine or a multiple. (e.g. 9×9= 81, 8+1 = ...

Any multiple of nine will have digits that add up to nine or a multiple. (e.g. 9×9= 81, 8+1 = 9; 9×5= 45, 4+5 = 9) – Waldo Weyeris

05/1/13 --