3000 Sudoku Puzzles, Printable Puzzle Pages, With Solutions ... - Free Printable

To solve Sudoku puzzles, we need to follow the basic rules of Sudoku:

1. Each row must contain the digits 1 through 9 without repetition.
2. Each column must contain the digits 1 through 9 without repetition.
3. Each 3x3 subgrid (also called a "box" or "region") must contain the digits 1 through 9 without repetition.

Let's solve Puzzle 15 step by step as an example. The puzzle is labeled as "Very Easy," so it should be straightforward to solve using basic techniques.

Puzzle 15:

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

#### Step 1: Fill in the obvious numbers
We start by looking for rows, columns, or boxes where only one number can fit in a particular cell.

- Row 2, Column 3: The only missing number in Row 2 is 8.
```
1 3 8 | 2 6 4 | 7 5 9
2 9 8 | 3 1 5 | 6
4 5 6 | 9 8 7 | 1 2 3
```

- Row 2, Column 7: The only missing number in Row 2 is 4.
```
1 3 8 | 2 6 4 | 7 5 9
2 9 8 | 3 1 5 | 4 6
4 5 6 | 9 8 7 | 1 2 3
```

- Row 6, Column 1: The only missing number in Row 6 is 8.
```
1 3 8 | 2 6 4 | 7 5 9
2 9 8 | 3 1 5 | 4 6
4 5 6 | 9 8 7 | 1 2 3
3 1 5 | 6 2 8 | 4
2 9 4 | 5 7 | 8 1
8 6 7 | 1 4 | 5 2 3
6 8 2 | 4 5 | 9 7
9 1 | 8 3 6 | 2 4 5
5 4 3 | 9 | 8 1 6
```

#### Step 2: Continue filling in the grid
We continue this process, focusing on rows, columns, and boxes where only one number can fit.

- Row 5, Column 8: The only missing number in Row 5 is 9.
```
1 3 8 | 2 6 4 | 7 5 9
2 9 8 | 3 1 5 | 4 6
4 5 6 | 9 8 7 | 1 2 3
3 1 5 | 6 2 8 | 4
2 9 4 | 5 7 9 | 8 1
8 6 7 | 1 4 | 5 2 3
6 8 2 | 4 5 | 9 7
9 1 | 8 3 6 | 2 4 5
5 4 3 | 9 | 8 1 6
```

- Row 4, Column 7: The only missing number in Row 4 is 9.
```
1 3 8 | 2 6 4 | 7 5 9
2 9 8 | 3 1 5 | 4 6
4 5 6 | 9 8 7 | 1 2 3
3 1 5 | 6 2 8 | 9 4
2 9 4 | 5 7 9 | 8 1
8 6 7 | 1 4 | 5 2 3
6 8 2 | 4 5 | 9 7
9 1 | 8 3 6 | 2 4 5
5 4 3 | 9 | 8 1 6
```

#### Step 3: Solve the rest of the puzzle
We continue this process until the entire grid is filled. After solving, the completed puzzle looks like this:

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

Final Answer:

The solved Puzzle 15 is:
```
1 3 8 | 2 6 4 | 7 5 9
2 9 8 | 3 1 5 | 4 6 7
4 5 6 | 9 8 7 | 1 2 3
------+-------+------
3 1 5 | 6 2 8 | 9 4 7
2 9 4 | 5 7 9 | 8 1 6
8 6 7 | 1 4 3 | 5 2 9
------+-------+------
6 8 2 | 4 5 1 | 3 7 9
9 1 3 | 8 3 6 | 2 4 5
5 4 9 | 7 9 2 | 8 1 6
```

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