| Step 18 | ||
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The purple highlighted square must have 1 and 5 (though in unknown order) in the two tiles indicated with green 1's and 5's (see step 10). The remaining two tiles (with the red x's) must be 3 and 6 The pink highlighted 6 eliminates one of these tiles. The other must be a 6, the eliminated one must be the 3.  | |
| Step 19 (basic) | ||
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