Money Counts

Strategies and Hints

The answer is:

First, M must equal 1, since the sum of different two one-digit numbers plus any regrouping (also the sum of different one-digit numbers) cannot exceed 18. Next, S must be 9 and O must be 0, since M and O are different. MO cannot be 11, and adding 1 to any digit-even with a carry-cannot give more than 11. These results lead to the conclusion that R = 8, since we must carry a 10 from the previous column. Lastly, considering the numbers we have used up, we must conclude that N = 6. Following this reasoning, we determine the values of the other variables finally arriving at Y = 2.