Mental Royale
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Hidden Triple

Working with Candidates8 / 32

Three digits confined to three cells — everything else is noise.

Three digits that appear only in the same three cells of a unit reserve those cells, exactly like a hidden pair one size up. All other candidates in the three cells can be erased.

Hidden triples are the trickiest of the subset family to spot: none of the digits has to appear in all three cells, and the cells usually carry plenty of camouflage.

See it in action

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Step 1 of 4

The setup

List where each digit can go in the unit. Digits with only two or three possible cells are the ingredients — look for three of them whose cells overlap into a set of exactly three. Step through this real position to see it happen.

Practice

Find the hidden triple and clear the unrelated candidates from its three cells.

Drill 1 of 29

Tap a cell, then the candidate digit you want to remove.