I have a problem to do in which letters represent numbers. The specific one I don't understand is SEND + MORE = MONEY. The "E's" are the same number in each word, as are the "N's" and "M's" and "O's". I figured out what the highest and lowest possible numbers SEND and MORE could be, but I don't know how to go about figuring the problem out, except for guess-and-check. If anyone has any ideas, please respond and give me some clues. Thanks.

Rachel