Steps 19-21
| Step 19 | ||
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Simple Elimination There are three empty tiles in the highlighted 3x3 square. The missing numbers are 2, 4 and 8. The highlighted 8 eliminates two of the empty tiles in the square, so the remaining empty tile must be an 8. |
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| Step 20 | ||
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Simple Elimination There are two empty tiles in the highlighted row. The missing numbers are 1 and 6. The highlighted 1 eliminates of them so the remaining empty tile must be a 1. |
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| Step 21 | ||
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Single Possibility There is only one empty tile in the highlighted row. The missing number is 6, and must be the value of that tile. |
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