Berikut adalah artikel tentang 0.42 x 0.21:

## Multiplying Decimals: A Step-by-Step Guide

Multiplying decimals can seem daunting at first, but it's actually quite straightforward. Let's take a look at how to multiply 0.42 by 0.21:

### 1. Ignore the decimal points

Start by treating the numbers as whole numbers: 42 x 21.

### 2. Multiply as usual

Perform the multiplication as you would with any whole numbers:

```
42
x 21
----
42
840
----
882
```

### 3. Count decimal places

Now, count the total number of decimal places in the original numbers (0.42 has two decimal places, and 0.21 has two decimal places, for a total of four decimal places).

### 4. Place the decimal

Starting from the rightmost digit of the product (882), count four places to the left and place the decimal point. This gives us **0.0882**.

### Therefore, 0.42 x 0.21 = 0.0882.

### Tips for multiplying decimals

**Visual aids:**You can use grid paper to visualize the multiplication of decimals.**Estimation:**Before you multiply, estimate the answer. This will help you catch any major errors.**Practice makes perfect:**The more you practice multiplying decimals, the easier it will become.