| Step 10 | ||
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The purple highlighted column is missing 5 tiles. Three of the missing numbers can be found in a square which has two of the column's empty tiles. That leaves only 3 tiles for those three numbers. Hence, only those numbers (1, 6, 9) can be in those tiles. The pink highlighted 6 and 9 both eliminate the same tile, which by the reasoning above can only be a 1, 6 or 9. Therefore, this tile must be a 1. | |
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