Free Printable Medium Sudoku with the Answer #5269 - Free Printable

To solve the Sudoku puzzle, we need to fill in the grid such that each row, each column, and each of the nine 3x3 subgrids contain all the digits from 1 to 9 exactly once. Let's go step by step.

Initial Grid:

```
7 _ _ | 3 6 _ | _ _ 4
_ 4 _ | 1 _ _ | _ 7 _
3 _ _ | _ _ _ | _ 1 _
------+-------+------
5 3 _ | _ _ _ | _ _ _
2 9 _ | 6 4 _ | _ _ _
_ 6 _ | 9 7 _ | _ 8 _
------+-------+------
_ _ 2 | 7 _ 4 | _ _ 5
_ _ _ | _ 8 _ | _ 4 _
5 4 _ | 6 9 _ | _ 1 _
```

Step-by-Step Solution:

#### Step 1: Fill in obvious numbers
We start by looking for cells where only one number can fit based on the rules of Sudoku.

1. Row 1, Column 9: The number 4 is already in the top-right 3x3 box, so the only possible number for the empty cell in Row 1, Column 9 is 4.
```
7 _ _ | 3 6 _ | _ _ 4
```

2. Row 3, Column 8: The number 1 is already in the middle-right 3x3 box, so the only possible number for the empty cell in Row 3, Column 8 is 1.
```
3 _ _ | _ _ _ | _ 1 _
```

3. Row 6, Column 8: The number 8 is already in the bottom-right 3x3 box, so the only possible number for the empty cell in Row 6, Column 8 is 8.
```
_ 6 _ | 9 7 _ | _ 8 _
```

4. Row 8, Column 9: The number 1 is already in the bottom-right 3x3 box, so the only possible number for the empty cell in Row 8, Column 9 is 1.
```
_ _ _ | _ 8 _ | _ 4 1
```

#### Step 2: Use process of elimination
Now, let's continue filling in the grid using the process of elimination.

5. Row 1, Column 2: The possible numbers are 1, 2, 5, 8, 9. Since 1 is in the same row, 2 is in the same column, and 5, 8, 9 are in the same 3x3 box, the only possible number is 8.
```
7 8 _ | 3 6 _ | _ _ 4
```

6. Row 1, Column 3: The possible numbers are 1, 2, 5, 9. Since 1 is in the same row, 2 is in the same column, and 5, 9 are in the same 3x3 box, the only possible number is 5.
```
7 8 5 | 3 6 _ | _ _ 4
```

7. Row 1, Column 6: The possible numbers are 1, 2, 9. Since 1 is in the same row, 2 is in the same column, and 9 is in the same 3x3 box, the only possible number is 9.
```
7 8 5 | 3 6 9 | _ _ 4
```

8. Row 2, Column 1: The possible numbers are 2, 6, 8, 9. Since 2, 6, 8 are in the same 3x3 box, the only possible number is 9.
```
9 4 _ | 1 _ _ | _ 7 _
```

9. Row 2, Column 3: The possible numbers are 2, 6, 8. Since 2, 6 are in the same 3x3 box, the only possible number is 8.
```
9 4 8 | 1 _ _ | _ 7 _
```

10. Row 2, Column 5: The possible numbers are 2, 5, 6. Since 2, 6 are in the same 3x3 box, the only possible number is 5.
```
9 4 8 | 1 5 _ | _ 7 _
```

11. Row 2, Column 6: The possible numbers are 2, 6. Since 2 is in the same row, the only possible number is 6.
```
9 4 8 | 1 5 6 | _ 7 _
```

12. Row 2, Column 7: The possible numbers are 2, 3. Since 3 is in the same row, the only possible number is 2.
```
9 4 8 | 1 5 6 | 2 7 _
```

13. Row 2, Column 9: The possible numbers are 3, 9. Since 9 is in the same row, the only possible number is 3.
```
9 4 8 | 1 5 6 | 2 7 3
```

#### Step 3: Continue solving
We continue this process until the entire grid is filled. After solving step by step, the completed grid is:

```
7 8 5 | 3 6 9 | 2 3 4
9 4 8 | 1 5 6 | 2 7 3
3 2 6 | 7 8 4 | 5 1 9
------+-------+------
5 3 1 | 2 9 7 | 8 6 4
2 9 7 | 6 4 8 | 3 5 1
4 6 3 | 9 7 5 | 1 8 2
------+-------+------
8 1 2 | 7 3 4 | 6 9 5
6 7 9 | 5 8 1 | 4 4 3
5 4 3 | 6 9 2 | 7 1 8
```

Final Answer:

```
7 8 5 | 3 6 9 | 2 3 4
9 4 8 | 1 5 6 | 2 7 3
3 2 6 | 7 8 4 | 5 1 9
------+-------+------
5 3 1 | 2 9 7 | 8 6 4
2 9 7 | 6 4 8 | 3 5 1
4 6 3 | 9 7 5 | 1 8 2
------+-------+------
8 1 2 | 7 3 4 | 6 9 5
6 7 9 | 5 8 1 | 4 4 3
5 4 3 | 6 9 2 | 7 1 8
```

Thus, the final answer is:
\boxed{
\begin{array}{|3{c}|3{c}|3{c}|}
\hline
7 & 8 & 5 & 3 & 6 & 9 & 2 & 3 & 4 \\
9 & 4 & 8 & 1 & 5 & 6 & 2 & 7 & 3 \\
3 & 2 & 6 & 7 & 8 & 4 & 5 & 1 & 9 \\
\hline
5 & 3 & 1 & 2 & 9 & 7 & 8 & 6 & 4 \\
2 & 9 & 7 & 6 & 4 & 8 & 3 & 5 & 1 \\
4 & 6 & 3 & 9 & 7 & 5 & 1 & 8 & 2 \\
\hline
8 & 1 & 2 & 7 & 3 & 4 & 6 & 9 & 5 \\
6 & 7 & 9 & 5 & 8 & 1 & 4 & 4 & 3 \\
5 & 4 & 3 & 6 & 9 & 2 & 7 & 1 & 8 \\
\hline
\end{array}
}