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Here are some tips for Decimal Multiplication, which aligns with Florida state standards:

Decimal Multiplication

You must know how to do long multiplication before doing this topic.
To review Long Multiplication, see here.

Steps for decimal multiplication:

1. Ignore the decimal points for now, and multiply as whole numbers.
2. Add the number of digits to the right of the decimal point for each decimal.
3. Place the decimal point in the answer.
Note: Be careful of zeros when doing decimal multiplication.   (See examples 2 and 3 below.)

Example 1:

Multiply: 3.2 × 0.4
Ignore the decimal points and multiply.
```    32
× 04
128
```
Figure out where to place the decimal point.
```    3.2   ← 1 digit to the right of the decimal point
× 0.4   ← 1 digit to the right of the decimal point
```
Place the decimal point in the answer.
```    3.2
× 0.4
1.28   ← 2 (1 + 1) digits to the right of the decimal point
```
3.2 × 0.4 = 1.28

Example 2: Adding zeros to place the decimal point

Multiply: 0.08 × 0.1
Ignore the decimal points and multiply.
```    8
× 1
8
```
Figure out where to place the decimal point.
```    0.08   ← 2 digits to the right of the decimal point
× 0.1   ← 1 digit to the right of the decimal point
```
Place the decimal point in the answer.
```    0.08
× 0.1
0.008   ← 3 (2 + 1) digits to the right of the decimal point
Add zeros when there are no more digits to the right.
```
0.08 × 0.1 = 0.008

Example 3: Remember the zeros!

Multiply: 0.35 × 1.6
Ignore the decimal points and multiply.
```   35
× 16
210
35
560
```
Figure out where to place the decimal point.
```  0.35   ← 2 digits to the right of the decimal point
× 1.6   ← 1 digit to the right of the decimal point
```
Place the decimal point in the answer.
```  0.35
× 1.6
0.560   ← 3 (2 + 1) digits to the right of the decimal point
Remember to count the first zero when placing the decimal!
```
0.35 × 1.6 = 0.56

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