Naked Subsets

Find two cells in a row, column or block that each contain only the same two candidates. Those digits must occupy the two cells, so remove them from every other cell in that group. Follow the pencil-note examples and interactive demo to see how eliminations help you make progress, and compare Naked Pairs with Hidden Pairs.

Find three cells in a row, column or block whose complete candidate lists contain only three digits between them. Those digits belong in the three cells, so remove them from the other cells in that group. The lists need not match. Follow the pencil-note examples and interactive demo to see how a triple can lead to a single or to further candidate eliminations.

Find four cells in a row, column or block whose complete candidate lists use only four digits between them. Reserve those digits for the four cells and remove them from other cells in that group. The lists need not match or contain all four digits. Follow the pencil-note examples and demo, compare complementary hidden subsets, and practice with prepared library puzzles.