Hello, Judi!
Code:
1 2 3
N R
+ R N
-----
A B C
The addition problem above is correct.
If N, R, A, B, and C are different digits,
what is the greatest possible value of ?
In column-1, we see that Code:
1 2 3
N R
+ R N
-----
1 B C
In column-3, we see that ends in
In column-2, we see that ends in
Then and there is a "carry" to column-2
. . where we have:
For maximum , let
. . But we find that this results in duplicated digits.
For we have: Code:
N 9
+ 9 N
-----
A B C
But we get:
. . (If , then )
Hence, neither nor can be
The next largest sum occurs for: and we have: Code:
8 7
+ 7 8
-----
1 6 5
Therefore: