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Roy Grandin · Joined: 17 May 2007 Posts: 1

I often have trouble with the Very Hard puzzles. 4 May was no exception. I could get to the same position as if you followed the Hints to move 13. After this I cannot see the logic for the 14th move, a 3 in Column 3 row 1. I could only get to that by trial and error.
Can anybody explain this logic to me using simple terms?

Steve R · Posted: Tue May 29, 2007 9:26 pm Post subject:

It’s good to hear from you, Roy. As to the puzzle…

There is an xy-wing pivoted on r8c2 with candidates (12). The pincers are r9c1, candidates (13), and r8c4, candidates (23).

Whether the pivot contains 1 or 2 one of the pincers must contain 3, which may therefore be eliminated from r8c3. There is then only one cell open to 3 in the third column.

Steve