Dividing decimals by 10

Quick answer

When you divide a decimal number by 10, you move the decimal point one place to the left. This makes the number ten times smaller.

Learning outcome

By the end of this page, you will be able to divide decimals by 10 and understand that the decimal point moves one place to the left to make the number ten times smaller.

Success signs:

• You can explain what happens to the decimal point when dividing by 10
• You can work out simple decimal division by 10
• You can apply this to real-life situations like sharing money or measuring ingredients
• You can check your answer makes sense (is smaller than the original number)

Why this matters

Dividing decimals by 10 is useful in many everyday situations. When you're shopping and need to share a price between friends, when you're cooking and need to halve a recipe, or when you're working with money, you'll often use this skill. It's also a building block for more complex maths, like dividing by 100 or 1000, and understanding how numbers change when they get smaller.

For example, if you have £3.40 and want to share it equally between 10 friends, each friend gets 34p. This is the same as dividing 3.40 by 10. It's a useful skill for managing money and solving real problems.

How it works

Dividing by 10 is like taking a number and making it ten times smaller. When we do this with decimals, we move the decimal point one place to the left. Let's break it down:

1. Look at the decimal number
2. Find the decimal point (it might be invisible if the number is a whole number)
3. Move the decimal point one place to the left
4. Add a zero if needed at the beginning

Here's how it works with a simple example:

If we have the number 5.6, and we divide it by 10:

• Start with 5.6
• Move the decimal point one place to the left
• This gives us 0.56

So 5.6 ÷ 10 = 0.56

Examples you can see

Let's look at a few examples to help you understand this better.

Let's try one more example using a real-life situation:

Example: You have 5.4 litres of juice and want to pour it equally into 10 glasses. How much juice goes in each glass?

• 5.4 litres ÷ 10 = 0.54 litres per glass

This means each glass gets 54 centilitres of juice.

Try it as a mini adventure

The Great Decimal Treasure Hunt

You are on a treasure hunt in a magical maths kingdom where all numbers have decimal points. Your mission is to find the secret treasure by dividing decimals by 10.

Your first clue says: "Start with 8.7 and divide by 10 to find the next number."

What is 8.7 ÷ 10?

• Move the decimal point one place to the left
• 8.7 becomes 0.87

So the next number is 0.87.

Second clue: "Take 0.87 and divide by 10 again."

• 0.87 becomes 0.087

Keep going through the kingdom, dividing each number by 10 to find the final treasure chest!

Common mistakes

• Mistake: Forgetting to move the decimal point
• Why it happens: The decimal point can be easy to miss, especially if it's not visible in whole numbers
• Fix: Always look for the decimal point, even if it's not written

• Mistake: Moving the decimal point the wrong way
• Why it happens: Sometimes children think dividing makes numbers bigger
• Fix: Remember that dividing by 10 makes numbers smaller, so move the decimal point to the left

• Mistake: Not adding zeros when needed
• Why it happens: Children might think they can just remove the decimal point
• Fix: If you run out of digits, add a zero at the beginning to show the decimal point moved

Parent and carer guide

Helping your child with dividing decimals by 10 is simple and fun! Here are some ways you can support them:

1. Practice together: Use everyday items like money or measuring cups to show how dividing by 10 makes things smaller
2. Use visual aids: Draw number lines or use place value charts to show the decimal point moving
3. Ask questions: "What happens to the number when we divide by 10?" "Does it get bigger or smaller?"
4. Be patient: It's normal for children to make mistakes at first. Encourage them to try again
5. Relate to real life: Use examples like sharing a pizza or dividing pocket money to show why this skill matters

Remember, your child's confidence is important. Celebrate their successes and help them learn from mistakes without pressure.

Practice questions

1. What is 6.3 ÷ 10?
2. What is 42.8 ÷ 10?
3. What is 0.7 ÷ 10?
4. What is 156.9 ÷ 10?
5. What is 3.0 ÷ 10?

Answers:

1. 0.63
2. 4.28
3. 0.07
4. 15.69
5. 0.3

FAQ

How do you divide a decimal by 10?

You move the decimal point one place to the left. This makes the number ten times smaller.

What happens to the decimal point when dividing by 10?

The decimal point moves one place to the left. If there isn't enough space, you add a zero at the beginning.

Why does dividing by 10 make a number smaller?

Because you're splitting the number into ten equal parts. Each part is one-tenth of the original size.

Can I divide any decimal by 10?

Yes, you can divide any decimal number by 10 using the same method.

What if I need to divide by 100 or 1000?

When dividing by 100, you move the decimal point two places to the left. For 1000, you move it three places to the left.