Multiplying Decimals Examples in Math
Start with the recap, study the fully worked examples, then use the practice problems to check your understanding of Multiplying Decimals.
This page combines explanation, solved examples, and follow-up practice so you can move from recognition to confident problem-solving in Math.
Concept Recap
Multiplying numbers that contain decimal points by first multiplying as if they were whole numbers, then placing the decimal point in the product based on the total number of decimal places in both factors.
Think of 0.3 \times 0.4 as \frac{3}{10} \times \frac{4}{10} = \frac{12}{100} = 0.12. When you multiply decimals, you're working with fractions of 10, so the answer gets smaller—not bigger.
Read the full concept explanation →How to Use These Examples
- Read the first worked example with the solution open so the structure is clear.
- Try the practice problems before revealing each solution.
- Use the related concepts and background knowledge badges if you feel stuck.
What to Focus On
Core idea: The total number of decimal places in the factors equals the number of decimal places in the product.
Common stuck point: Understanding why multiplying two numbers less than 1 gives an even smaller number (0.5 \times 0.5 = 0.25).
Sense of Study hint: Ignore the decimals at first, multiply as whole numbers, then count total decimal places in both factors to place the point.
Worked Examples
Example 1
easySolution
- 1 Think of \(0.4\) as \(4 \times 0.1\).
- 2 \(0.4 \times 3 = (4 \times 0.1) \times 3 = 4 \times 3 \times 0.1 = 12 \times 0.1 = 1.2\).
- 3 Or: multiply \(4 \times 3 = 12\), then place decimal: 1 decimal place → \(1.2\).
Answer
Example 2
mediumPractice Problems
Try these problems on your own first, then open the solution to compare your method.
Example 1
easyExample 2
mediumRelated Concepts
Background Knowledge
These ideas may be useful before you work through the harder examples.