How does a shopkeeper use maths?

Quick answer

Shopkeepers use maths every day to count money, add up prices, give change, and keep track of stock. They use addition, subtraction, and sometimes multiplication to make sure customers get the right amount of change and that they have enough products to sell.

Learning outcome

By the end of this page, you will understand how a shopkeeper uses maths to add up prices, give correct change, and manage their stock – and you’ll be able to try some of these maths skills yourself!

• You can add prices of items to find a total cost
• You can subtract to find how much change a customer should get
• You can count items in groups to manage stock
• You can use simple maths to help a shop run smoothly

Why this matters

Shopkeepers use maths to make sure they give the right amount of change, know how many items they have left, and can sell the right number of products. It’s not just about numbers – it’s about helping customers and making sure the shop works well. Whether you're shopping at a store or helping at home, these maths skills are useful for everyone!

How it works

Let’s imagine you are a shopkeeper. You need to do a few things with maths:

1. Add up prices to find how much a customer owes
2. Give correct change when someone pays more than the total
3. Count stock to know how many items you have
4. Use multiplication when items are sold in groups

Let’s explore each of these one by one.

Examples you can see

Let’s imagine a shop that sells apples and bananas.

Example 1: Adding prices

You sell apples for 50p each and bananas for 30p each. A customer buys 2 apples and 3 bananas.

• 2 apples = 2 × 50p = 100p = £1.00
• 3 bananas = 3 × 30p = 90p
• Total = £1.00 + 90p = £1.90

Example 2: Giving change

The customer gives you £2.00.

• Change = £2.00 – £1.90 = 10p

Example 3: Counting stock

You have 24 apples in a box. You sell 6 apples.

• Remaining apples = 24 – 6 = 18 apples

Example 4: Using multiplication

You sell packs of 6 stickers. If someone buys 3 packs, how many stickers do they get?

• 3 × 6 = 18 stickers

Try it as a mini adventure

Adventure: The Shopkeeper’s Day

You are a shopkeeper today. You need to:

1. Count how many apples you have in 4 boxes, with 8 apples in each box
2. Calculate how much 3 oranges cost if each orange is 40p
3. Give change if someone pays £2.00 for items that cost £1.60
4. Check if you have enough bananas to sell 5 customers, each buying 2 bananas

Let’s go through each step together!

Step 1: Count apples

4 boxes × 8 apples = 32 apples

Step 2: Cost of oranges

3 oranges × 40p = 120p = £1.20

Step 3: Give change

£2.00 – £1.60 = 40p

Step 4: Check bananas

5 customers × 2 bananas = 10 bananas needed

If you have 12 bananas, you have enough!

Common mistakes

• Mistake: Adding up prices and forgetting to convert pence to pounds
• Why: It’s easy to mix up 100p = £1.00
• Fix: Always remember that 100p = £1.00, and count in pounds and pence separately

• Mistake: Giving too much or too little change
• Why: Subtracting the wrong way around
• Fix: Always subtract the total from the amount paid

• Mistake: Counting stock wrong when items are in groups
• Why: Not using multiplication
• Fix: Use multiplication to count large groups quickly

Parent and carer guide

Helping your child with shopkeeper maths is easy and fun!

1. Practice at home: Set up a pretend shop with toys or food items. Let your child set prices and calculate totals.
2. Real-life shopping: When you go shopping, ask your child to add up the prices of items before checkout.
3. Change games: Give your child £5 and let them buy items that cost less than £5, then calculate how much change they get.
4. Counting stock: Ask how many items are in a pack or box and how many packs you have to find the total.
5. Encourage thinking: Ask questions like “How much more do we need to sell to make £10?”

Remember: it’s okay to make mistakes. The goal is to learn and enjoy the process!

Practice questions

1. What is the total cost of 3 pencils at 20p each?
2. If a customer pays £1.00 for items that cost 75p, how much change should they get?
3. A shop has 6 boxes of 10 eggs. How many eggs are there in total?
4. If 2 bags of crisps cost 40p, how much do 5 bags cost?
5. How much would 4 toys at 50p each cost?

Answers:

1. 3 × 20p = 60p
2. £1.00 – 75p = 25p
3. 6 × 10 = 60 eggs
4. 2 bags = 40p, so 1 bag = 20p. 5 bags = 5 × 20p = 100p = £1.00
5. 4 × 50p = 200p = £2.00

FAQ

How do shopkeepers add up prices?

Shopkeepers add prices by using addition. For example, if a customer buys 2 items that cost £1.50 and £2.00, they add them together: £1.50 + £2.00 = £3.50.

Why do shopkeepers need to know multiplication?

Multiplication helps them quickly count items in groups, like 5 boxes with 10 stickers each, so 5 × 10 = 50 stickers.

What happens if a shopkeeper gives the wrong change?

If they give too much or too little, they might lose money or upset customers. That’s why it’s important to double-check!

Can I practice shopkeeper maths at home?

Yes! You can set up a pretend shop with toys or food, and practice adding prices, giving change, and counting stock.

Is shopkeeper maths only for big shops?

No! Even small shops, markets, or lemonade stands use the same maths. It’s a useful skill for everyone!