Question

se the traditional method or rectangular method to solve the problem.
345 x 21

Answer 1

To solve the multiplication problem \( 345 \times 21 \) using the traditional or rectangular method, you can follow these steps:

1. **Setting up the problem**: Write the numbers in a column, with \( 345 \) on top and \( 21 \) below it.

```
345
x 21
```

2. **Multiply the bottom number (1) by the top number (345)**:
- \( 1 \times 345 = 345 \)

Write this result below the line.

```
345
x 21
-----
345 (This is 345 * 1)
```

3. **Multiply the bottom number (2) by the top number (345)**, but remember that this 2 is in the tens place (which is actually \( 20 \)):
- \( 2 \times 345 = 690 \)
- Since you are multiplying by 20, you add a zero to this result:

```
345
x 21
-----
345 (This is 345 * 1)
+6900 (This is 345 * 20, i.e., 690 with one zero)
```

4. **Add the results together**:

```
345
+6900
-----
7245
```

So, \( 345 \times 21 = 7245 \).