| Step 20 | ||
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The purple highlighted square is missing the number 6. the red highlighted 6 eliminates two of the empty tiles. One of the remaining three empty tiles must be the 6. Since they are all on the same row, no matter which one it is, nothing else on this row can be a 6. The gray highlighted column below is missing the number 6. The pink highlighted 6's eliminate all but one of the empty tiles. Only one possible tile remains for the 6. | |
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