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Naked Pair, Triplet, Quad

(Locked Set, Naked Subset, Disjoint Subset)
challenging

If a container has a pair of cells that have just two possible digits, you can eliminate those digits from all the other cells in the container, a strategy called a “naked pair” or more generally a “naked subset”. It works with any number of cells - three cells that contain the same three digits are a “naked triplet”, four cells that contain the same four digits form a “naked quad”, and so on.

The following partially completed puzzle (from my Challenging collection) contains a couple naked pairs, which I've highlighted. In their respective rows, you can eliminate the numbers I've circled.

The next puzzle contains several naked pairs and triplets, of which I've highlighted two.

Notice that in the triplet in row 1, it is not necessary for each of the three cells to contain all three digits. Between them, the three cells will contain just the digits 2, 4, and 8, so we can eliminate those digits from all the other cells in the top row.

Can you find the others naked pairs and triplets in this puzzle?

So why is this technique called naked subset? Simply because if you mark all the possibilities for each cell, these cells stand out because they are the only ones with certain candidates and no others. Contrast this to hidden subsets.