Maths
Money maths: interest, sale prices and budgets
Practise percentages and everyday calculations with savings, sale prices, VAT, currency conversion and a club-trip budget. Worked examples show how to set out a calculation and check whether the result is sensible before pupils try a related problem.
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Practise percentages and everyday calculations with savings, sale prices, VAT, currency conversion and a club-trip budget. Worked examples show how to set out a calculation and check whether the result is sensible before pupils try a related problem.
Complete resource. Use the preview for diagrams and layout.
Page 1
MATHS AGES 11 TO 14 MONEY Financial maths Study each worked example, then try the next one. NAME CLASS DATE LEARNING GOAL Use percentages to work out simple interest, sale prices and VAT, and check each answer is sensible. SUCCESS CRITERIA I can write the sum, then calculate it. I can give my answer in £. I can check my answer looks sensible. E N T R Y WORKED EXAMPLE £200 is saved at 5% per year for 3 years. Find the interest and the total. YOUR TURN £500 is saved at 4% per year for 2 years. Find the interest and the total. WRITE IT interest = £200 × 0.05 × 3 CALCULATE interest = £30 ANSWER IN £ Total = £200 + £30 = £230 total = £ CHECK £30 is small next to £200. Sensible. Sensible? Because 1 SIMPLE INTEREST E N T R Y WORKED EXAMPLE A £40 jacket is reduced by 15%. Find the reduction and the sale price. YOUR TURN £60 trainers are 25% off. Find the reduction and the sale price. WRITE IT reduction = £40 × 0.15 CALCULATE reduction = £6 ANSWER IN £ Sale price = £40 − £6 = £34 sale price = £ CHECK £34 is less than £40. Sensible. Sensible? Because 2 SALE PRICE E N T R Y WORKED EXAMPLE A £50 item has 20% VAT (a tax) added. Find the VAT and the total. YOUR TURN An £80 item has 20% VAT added. Find the VAT and the total. WRITE IT VAT = £50 × 0.20 CALCULATE VAT = £10 ANSWER IN £ Total = £50 + £10 = £60 total = £ CHECK £60 is more than £50. Sensible. Sensible? Because 3 VAT Financial maths application Page 1 of 2
Page 2
MATHS AGES 11 TO 14 MONEY Currency and budgets NAME CLASS DATE E N T R Y Currency TIMES TIMES DIVIDE NOTES TO SELF RATE A made-up rate for practice: £1 = €1.20 WHICH WAY? Going £ to € gives more euros. Going € to £ gives fewer pounds. 4 WORKED EXAMPLE £150 SUM 150 × 1.20 = €180 YOUR TURN £35 SUM = € NOW GO BACK €90 SUM = £ E N T R Y Percentage increase A game costs £80. Next month it costs £92. Fill in each step. THEN SO 5 INCREASE £92 − £80 = £ DIVIDE BY THE START increase ÷ £80 = AS A PERCENTAGE × 100 = % E N T R Y Budget A club trip Complete the totals. Then see whether the money left balances. INCOME £ Fundraising 80 Gift 40 Total income SPENDING £ Hall hire 45 Snacks 30 Equipment 25 Prizes 15 Total spending 6 MONEY LEFT income − spending = £ WHAT IF? The hall costs £50. Spending £ money left £ E N T R Y Go further. In Entry 5, why is the answer 15% and not £12? Write in sentences. 7 Financial maths application Page 2 of 2
A teaching sequence
Calculate simple interest, percentage reductions and additions, currency amounts and a basic budget, showing working and units.
Calculate interest and reductions
Calculate simple interest from starting savings, yearly rate and years, then add it to the original amount. For sale prices, subtract the calculated reduction and check that the result is lower.
Should your sale price be below the starting price?
Add the stated practice VAT
For VAT, calculate the stated 20% amount and add it to the original price. Check that the total is higher.
Does the final total exceed the original price by the calculated tax amount?
Use the fictional exchange rate
Use the printed made-up rate to convert between pounds and euros. Decide whether to multiply or divide by describing which currency amount should be larger.
Does multiplying or dividing match the direction of conversion?
Review percentage and budget changes
Calculate percentage increase from the starting value and complete the club's income, spending and money left. Estimate, then test the changed hall-hire cost and explain its effect.
Why is the increase a percentage of the starting value rather than a currency amount?
Before you teach
Look for the thinking behind an answer, choose the support your class needs and leave room for an independent response.
What to look for
Check that the percentage is written in a usable form, the operation matches the question and the answer includes pounds or euros where needed. For the budget, total income minus total spending should equal money left. Ask pupils to make a rough estimate before accepting an exact answer.
Give a little support
Use a calculator or percentage grid if arithmetic is not the lesson focus. Ask pupils to underline the starting amount, circle the rate and write the intended operation before calculating. Work through the exchange-rate direction with a simple estimate.
Take the idea further
Ask pupils to change one budget item and calculate how much fundraising would be needed to reach a chosen total. They can compare a percentage increase with a fixed cash increase and explain how the starting amount affects the result.
Things to keep in mind
The numbers are practice examples, not financial advice. The exchange rate is explicitly made up, the interest example assumes simple interest and the stated VAT rate is used only for arithmetic practice. Check current local tax or currency information separately when discussing real purchases.
Keep the idea. Make it yours.
Bring your topic, learning goal and class context to PLAI™, then review what you create.
Ideas to try with your class
Sample teaching perspectives on what to try, what to adapt and what to watch for.
Meet The Creators
Meet a creator whose teaching interests connect with this template.
Clear Example
The two-page worksheet models simple interest, a sale reduction and VAT before changing the values for practice. A made-up £1-to-€1.20 rate supports the currency task, with a later budget section.
Good Question
For ages 11 to 14, each example pairs working with a reasonableness check: interest should be small beside principal, a sale price below the original, and a VAT total above it. The check asks pupils to explain why.
Calm Table
The repeated “write it, calculate, answer in £, check” structure helps keep method and unit together. Complete one worked example before the pupil attempts the parallel values.
Spare Pencil
The exchange rate is explicitly made up, and the interest examples use simple interest only. Do not present the figures as current rates, financial advice or a full account of tax calculations.