Kakuro: sum 17 in 2 cells
A sum of 17 in 2 cells has exactly one digit set: 8+9.
| Combination | Digit set |
|---|---|
| 8 + 9 | 89 |
What this tells you
- Unique. There is only one possibility, so as soon as you see this clue on a run of 2 cells you know the digits 8, 9 go in it. Only their order is open, and crossing runs usually decide that.
- Digits that can never appear: 1, 2, 3, 4, 5, 6, 7. You can remove them from every cell of the run.
Related sums
The digits left out of each combination form a combination for the mirror run: sum 28 in 7 cells.