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[togar1]

I have a hard time spotting when to use which of the more advanced techniques.

What approach would you take next on this puzzle and why?

Thanks


. . 5 | . . 2 | . 9 .
4 . 6 | 7 8 . | . . .
. . . | . . . | . . .
-------+-------+------
. 7 8 | 2 . . | 4 . .
2 . . | 8 4 6 | . . 9
. . 4 | . 7 3 | 8 2 .
-------+-------+------
. . . | . . 8 | 9 . .
. . . | . 2 7 | 6 8 5
. 8 . | 5 . . | 1 . .

[keith]

In this puzzle, note that the <2> in block 3 must be in C7. So, <2> is not a possibility in R1C9, R2C9, or R3C9.

Also, the <5> in B4 must be in R6. Now, there is a pair <13> in B4 and a pair <13> in C2. So, eliminate <13> as possibilities in other squares in B4 and C2.

Notice that five squares in B3 contain <12357> and so the other three unsolved squares can contain only <468> as possibilities.

If you continue on in this way, you will solve the puzzle.

Keith