Naked Single
Only one digit remains possible for this cell — place it.
How it works
- 1This cell sits where an across run and a down run cross, so it has to satisfy both.
- 2The across run is 17 over two cells, and only 8 + 9 reaches that — so this cell is an 8 or a 9.
- 3The down run is 16 over two cells, and only 7 + 9 reaches that — so it is a 7 or a 9.
- 4One digit is on both lists and nothing else is. Place the 9.
- Cells that establish the pattern
- Where the conclusion lands