Philippa M. Rhodes
In these problems, each letter represents a digit, and different letters represent different digits. You are to find which digit each letter represents. Some problems have more than one solution.
E, R, and T have to be even numbers since they are 2A, 2L, and 2D, respectively. This poses a problem when trying to find O so that O + E = O. Either E or O must be 9 and N + R = 10 + B. Since E is even, it can not be 9, and if O is 9, then E must be 9 also in order for 1 + O + E = O. So, this problem is not solvable (if we do not use zero).