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To the right is an example of a partial Sudoku puzzle. Using only the given information, there is a way for you to locate the position of a "1" on the grid. Can you figure it out? Move your mouse over the puzzle to reveal the answer. The correct position will be highlighted in green.

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Step-by-Step Explanation:

1. Look at the first row and the first column. You can't place a "2" or a "3" in the first row or the first column because there is already a "2" and a "3" in both the first row and the first column. The first row and the first column are darkened because a "2" or a "3" can't go in either the first row or the first column.
2. Look at the 3x3 block in the upper left corner. A "2" and a "3" have to go somewhere in this box because of the rules. The "2" and the "3" can't go in any of the darkened areas, and they obviously can't go in the boxes where the "4" and the "5" are. This only leaves the two square that are highlighted yellow.
3. Look at the first row and the third row. Neither row can have any additional "1"s because both already have a "1." The first row and the third row are darkened because a "1" can't go in either row.
4. Look at the 3x3 block in the upper left corner. A "1" has to go somewhere in this box because of the rules. The "1" can't go in any of the darkened areas or the locations of the "2" and the "3," and it obviously can't go in the boxes where the "4" and the "5" are. This only leaves the square that is highlighted green.