Multiply and divide by 100
Use charts and sliders to explain two-place shifts.
Quick answer
When you multiply a number by 100, you move each digit two places to the left. When you divide a number by 100, you move each digit two places to the right.Learning outcome
By the end of this page, you will understand how multiplying and dividing by 100 changes the place value of each digit in a number. Success signs:- You can explain why multiplying by 100 makes a number bigger
- You can show how digits move when you multiply or divide by 100
- You can solve simple multiplication and division problems with 100
- You can use place value charts to help you work out the answers
Why this matters
Multiplying and dividing by 100 helps you understand how numbers work. You use this in real life when you:- Measure things in metres and centimetres
- Count money in pounds and pence
- Work out how much you spend or save
- Play games that involve scores or points
How it works
Think of place value like a row of houses. Each house has a number, and each number has a special job:- The ones house (rightmost) is worth 1
- The tens house is worth 10
- The hundreds house is worth 100
- The thousands house is worth 1,000
- Start with any number, like 45
- Write it in a place value chart
- Multiply by 100: move each digit two places left
- Divide by 100: move each digit two places right
Examples you can see
Let's start with a simple example: 63 Step 1: Write it in a place value chart| Hundreds | Tens | Ones |
|---|---|---|
| 0 | 6 | 3 |
| Hundreds | Tens | Ones |
|---|---|---|
| 6 | 3 | 0 |
| Hundreds | Tens | Ones |
|---|---|---|
| 0 | 0 | 63 |
| Number | × 100 | ÷ 100 |
|---|---|---|
| 27 | 2,700 | 0.27 |
| 154 | 15,400 | 1.54 |
| 8 | 800 | 0.08 |
| 300 | 30,000 | 3 |
Try it as a mini adventure
Adventure: The Magic Shop You are the shopkeeper of a magical store where everything costs 100 times more than normal! You have 12 items:- 1 pencil = 10p
- 1 ruler = 20p
- 1 eraser = 5p
- 1 pen = 15p
- 1 notebook = 25p
- 1 highlighter = 8p
- 1 sharpener = 12p
- 1 calculator = 30p
- 1 compass = 18p
- 1 protractor = 22p
- 1 set of coloured pencils = 35p
- 1 geometry kit = 45p
- 1 pencil = 10p × 100 = 1,000p = £10
- 1 ruler = 20p × 100 = 2,000p = £20
- 1 eraser = 5p × 100 = 500p = £5
Common mistakes
- Mistake: Thinking 45 × 100 = 450
Why it happens: Confusing with multiplying by 10 instead of 100
Fix: Remember that × 100 means moving two places, not one - Mistake: Thinking 700 ÷ 100 = 70
Why it happens: Thinking you're dividing by 10 instead of 100
Fix: Remember that ÷ 100 means moving two places, not one - Mistake: Forgetting to add zeros when multiplying by 100
Why it happens: Not understanding place value shifts
Fix: Use a place value chart to see where digits go - Mistake: Thinking 0.5 × 100 = 5
Why it happens: Confusing decimal and whole number place value
Fix: 0.5 = 5 tenths. When we multiply by 100, we get 500 hundredths = 5
Parent and carer guide
You can help your child understand multiplying and dividing by 100 by:- Using a place value chart together
- Playing the magic shop game
- Looking at real money amounts
- Using everyday examples like measuring
- "Let's see where each digit goes when we multiply by 100"
- "Think of it like moving houses - each digit gets a new home two places away"
- "What happens when we divide by 100?"
- Children might make mistakes at first - that's normal
- They don't need to memorize every fact right away
- Using visual aids like charts helps them understand
Practice questions
- What is 34 × 100?
- What is 870 ÷ 100?
- What is 5 × 100?
- What is 6,000 ÷ 100?
- What is 123 × 100?
- What is 1,230 ÷ 100?
- What is 70 × 100?
- What is 9,000 ÷ 100?
- What is 200 × 100?
- What is 3,500 ÷ 100?
- 3,400
- 8.7
- 500
- 60
- 12,300
- 12.3
- 7,000
- 90
- 20,000
- 35
FAQ
Why does multiplying by 100 move digits two places?
Because 100 = 10 × 10, and each multiplication by 10 moves digits one place. So 100 moves them two places.
Can I use this with decimal numbers?
Yes! For example, 0.4 × 100 = 40. The decimal point moves two places to the right.
How can I remember which way to move digits?
Remember: Multiply = move left. Divide = move right. And always move two places for 100.
What if I have a number with zeros?
That's fine! For example, 200 × 100 = 20,000. The zeros stay but the other digits move.
Is this the same as multiplying by 10 twice?
Yes! 10 × 10 = 100, so multiplying by 100 is the same as multiplying by 10 twice.