A naked pair is when two cells in a house contain exactly the same two candidates.
Understanding the Concept
Also called "Naked Couple" or "Conjugate Pair".
When two cells in a row, column, or box have only the same two candidates, those two digits must go in those two cells.
Therefore, these two candidates can be eliminated from all other cells in that house.
It doesn't matter which digit goes where - they're locked to those two cells.
Example: If two cells both have only candidates {2,7}, then 2 and 7 can't go anywhere else in that house.
This is called "naked" because the pair is obvious when looking at candidates.
Examples
Naked Pair in Row
If R3C2={4,8} and R3C7={4,8}, then 4 and 8 can be removed from all other cells in row 3.
Naked Pair in Box
Two cells in box 5 both showing {3,9} form a naked pair. Remove 3 and 9 from other cells in box 5.
Pro Tips
- •Look for cells with exactly 2 candidates
- •Check if another cell in the same house has the same 2 candidates
- •The pair "claims" both digits for themselves
- •Often leads to naked singles in other cells
