GridWits
Medium tier Technique 7 of 20 Used by Smart Hint

Naked Pair

Two cells in a run share the exact same two candidate digits — remove those digits from the rest of the run.

How it works

  1. 1The first two cells are both down to the same two digits, {3, 4}.
  2. 2Whichever way round they fall, between them they use up the run's 3 and its 4 — no other cell in the run can have either.
  3. 3Strike 3 and 4 from the last cell. That leaves it just 9 — and 3 + 4 + 9 is exactly the run's 16.
16 3 4 3 4 3 4 9
  • Cells that establish the pattern
  • Where the conclusion lands
  • Digit ruled out
Next in the ladder Hidden Pair →

Two digits guaranteed to appear in this run only fit in the same two cells — strip those cells down to just those two.