Naked Pair
nakedPair
LevelNot seen in a hint yet
How it works
If two cells in the same house hold exactly the same two candidates, those two digits take those two cells one each. Which goes where is still unknown, but that the pair uses up both cells is certain.
So both digits can be removed from every other cell of that house. The pair is naked — visible without counting anything. The same shape with three cells is a Naked Triple.
Worked example
3
8
4
5
9
4
8
5
5
3
8
4
9
2
5
6
4
1
8
7
3
1
6
8
3
5
7
4
3
4
7
9
2
8
6
1
3
5
9
4
8
6
8
4
6
1
6
9
4
8
1
3
2
● evidence✕ eliminated★ confirmed
In row 3, the 2 cells R3C3, R3C4 have no candidates other than 2, 7 (marked ●).
Those 2 cells share 2, 7 between them, so those digits are removed from the other 3 cells of row 3 (✕).
Examples I encountered
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