Mathematics classroom notes
Year 4 - Money — calculating change in Australian money
Strand / topic: Number and Algebra / Money — calculating change in Australian money
Based on Pi Leo Academy's Victorian Curriculum F-10 Mathematics year-level guide and aligned to NAPLAN-style mathematical reasoning. Official curriculum code: Not stated in the provided curriculum source.
By the end of this note, students should be able to explain money — calculating change in australian money, use a clear method, solve simple and test-style questions, and check their answers for Year 4 Number and Algebra work.
It helps with shopping, saving, budgeting and checking change in Australian dollars and cents. This topic builds the reasoning, fluency and confidence students need for future NAPLAN-style questions and everyday mathematics.
1 What this means
Money questions use dollars and cents, often with totals, change, discounts or simple financial decisions.
Money problems are really place-value problems with dollars and cents. In Year 4, students should connect the words in the question to a model such as a diagram, table, number line, grid, formula or equation. They then work in small steps and check whether the answer matches the question, the units and the size of the numbers.
- Use Australian dollars and cents, with 100 cents making $1.
- Write money with two decimal places when using dollar notation.
- For change, subtract the cost from the amount paid.
- Check that the change is less than the amount paid.
Use this visual to organise money — calculating change in australian money before calculating.
Keep dollars and cents lined up like decimal place values.
2 Important rules / ideas
Use $ for dollars and c for cents; $1 = 100c.
Write $4.50, not $4.5, in formal money answers.
Change = amount paid - cost.
Important vocabulary
Whole Australian money units.
100 cents make 1 dollar.
The amount altogether.
Money returned after paying more than the cost.
3 Step-by-step method
- List each cost in dollars and cents.
- Add costs or subtract from the amount paid.
- Write money with two decimal places.
- Check that change is less than the amount paid.
4 Worked examples
Add $3.40 and $2.25.
- Add dollars and cents carefully.
- $3.40 + $2.25 = $5.65.
You pay $10 for an item costing $6.75. Find the change.
- Change = $10.00 - $6.75.
- Subtract to get $3.25.
- The change is $3.25.
Three notebooks cost $4.50 each. Find the total.
- Multiply $4.50 by 3.
- $4 x 3 = $12 and 50c x 3 = $1.50.
- Total = $13.50.
A bus fare is $2.80 each way. How much for a return trip?
- A return trip has two fares.
- $2.80 x 2 = $5.60.
- The return trip costs $5.60.
5 More examples
Write 375c in dollars.
100c = $1, so 375c = $3.75.
Pay $20 for a $13.80 item.
$20.00 - $13.80 = $6.20 change.
NAPLAN-style thinking
In NAPLAN-style questions, money — calculating change in australian money may appear as a short calculation, a word problem, a diagram, a table or a multi-step reasoning question. Students should slow down and decide what the question is really asking before calculating.
Estimate first and eliminate answers that are too small, too large or use the wrong unit.
Write only the answer required, but use working on paper to avoid mental slips.
Circle the numbers, underline the action words and decide whether all numbers are needed.
Do one step at a time and label intermediate answers so the final step is clear.
6 Common mistakes
Write money with two decimal places.
Remember 100 cents is $1.
Subtract the cost from the amount paid.
- Choosing the first operation seen in the wording.
- Forgetting units, labels or place value.
- Stopping after the first step when the question asks for a final comparison.
7 Tips to remember
Use $7.90, not $7.9, for formal money writing.
Change can be checked by counting from the cost to the amount paid.
Use Australian coins and notes when making examples at home.
Parent teaching tips
- Ask your child to explain the method aloud before writing the answer.
- Use a real-life context at home, such as shopping, cooking, sport scores, maps or timetables.
- Praise clear working and checking, not only speed.
- Encourage a quick diagram or table for word problems before calculating.
Remember
Use two decimal places for dollars and cents.
8 Quick practice
- Add $3.40 and $2.25.
- You pay $10 for an item costing $6.75. Find the change.
- Three notebooks cost $4.50 each. Find the total.
- A bus fare is $2.80 each way. How much for a return trip?
9 Answers / explanation
Question 1
Answer: $3.40 + $2.25 = $5.65.
Add dollars and cents carefully. $3.40 + $2.25 = $5.65.
Question 2
Answer: The change is $3.25.
Change = $10.00 - $6.75. Subtract to get $3.25. The change is $3.25.
Question 3
Answer: Total = $13.50.
Multiply $4.50 by 3. $4 x 3 = $12 and 50c x 3 = $1.50. Total = $13.50.
Question 4
Answer: The return trip costs $5.60.
A return trip has two fares. $2.80 x 2 = $5.60. The return trip costs $5.60.
Extension challenge
Create your own multi-step question for this topic using an Australian context, then solve it and explain each step.
Hint: Use shopping, sport, maps, timetables, weather, school events or measurement at home.
Answer guide
Answers will vary. A strong answer includes clear working, correct units and a final sentence.
Quick revision
- Know what money — calculating change in australian money is asking you to find.
- Choose a diagram, table, formula, number line or equation before calculating.
- Show enough working that you can find and fix mistakes.
- Check the final answer, units and reasonableness.