Naked Pair
From Sudopedia
Jump to navigationJump to searchA Naked Pair is a Naked Subset of size 2.
It is formed by 2 cells that have candidates for only 2 digits and are collocated in the same house.
How it works
Pay attention to the cells r1c7 and r3c7 (highlighted in yellow) in the 7th column, which only have the two digits 5 and 6 as candidates. Therefore, the digits 5 and 6 must go into these two cells. This means that 5 and 6 can be eliminated in the remaining cells in the 7th column, so r6c7<>5 and r7c7<>6.
Incidentally, the r1c7 and r3c7 are also collocated in the same box, which is the 3rd one. Using the same logic leads to r1c9<>5, r1c9<>6 and r3c8<>6.
