Mike J answered I will do this step by step for you 15 + 47______ 62 Okay, now, add 5 and 7 (12). However, you can not put 12 down, so put the 2 down and carry the 1 to the other side. Next, add 4 and 1 (5) and then add that extra 1 (6). Put that 6 down and you will get 62 for your sum.