AQA GCSE Mathematics Paper 2 (Foundation), June 2025: Question 12
2 marks · Easy difficulty · Short Answer
Calculate the total cost of 7 apples given that 4 apples cost £2.20.
Practise this questionQuestion
Mark scheme
Show the mark scheme
How to answer it
Direct Proportion: The Unitary Method
📋 What this question tests
This question assesses your ability to solve direct proportion problems in a financial context:
- Using the unitary method (finding the cost of 1 item first).
- Converting accurately between pounds (£) and pence (p).
- Writing money values in correct decimal notation.
Question 12 Walkthrough
4 apples cost £2.20. Work out the cost of 7 of these apples. [2 marks]
📐 Step-by-Step Calculation
Method 1: Unitary Method (Recommended)
- Find the cost of 1 apple:
£2.20 ÷ 4 = £0.55 (or 220p ÷ 4 = 55p )
Earns M1 - Multiply by the target number (7 apples):
7 × £0.55 = £3.85 (or 7 × 55p = 385p)
Earns A1
Method 2: Multiplier (Scale Factor)
Scale factor = 7 ÷ 4 = 1.75
Total cost = 1.75 × £2.20 = £3.85
✅ Correct Answer
On the answer line:
Answer: £ 3.85
Mark Breakdown:
• M1: For 2.20 ÷ 4 , 0.55 , 220 ÷ 4 , or 55 .
• A1: For fully correct final value 3.85 .
• M1: For 2.20 ÷ 4 , 0.55 , 220 ÷ 4 , or 55 .
• A1: For fully correct final value 3.85 .
💡 Key Knowledge
- Direct Proportion: If the quantity of apples increases, the cost increases by the exact same multiple.
- The Unitary Method: Always find the value of one single unit by dividing total cost by initial quantity:
Cost of 1 item = Total Cost ÷ Number of Items - Working in Pence: If dividing decimals like £2.20 is difficult without a calculator, convert to pence first ( £2.20 = 220p ), divide, and then convert back by dividing by 100.
🧠 Exam Technique & Examiner Insight
- Look at the pre-printed unit: The answer line already has a £ sign. Make sure your number matches that unit!
- Show your working clearly: Even if you make an arithmetic mistake on the second step (e.g. 7 × 0.55), writing £2.20 ÷ 4 = £0.55 guarantees you score the method mark (M1).
- Sanity check: 7 is nearly double 4, so the answer should be a little less than double £2.20 (£4.40). £3.85 makes complete sense.
❌ Common Errors & Traps to Avoid
- Unit mismatch trap: Writing 385 on the answer line next to the printed £ symbol gives £385! This loses the accuracy mark (M1 A0) unless you explicitly cross out the £ sign and write "p".
- Additive error: Thinking "7 apples is 3 more than 4, so add £3" or similar addition tricks. Direct proportion requires multiplication and division, not addition.
- Decimal division slip: Writing £2.20 ÷ 4 = 0.52 or 0.50. Use short division (bus stop method) on 220 ÷ 4: 4 into 22 is 5 remainder 2, 4 into 20 is 5, giving 55p.
Topics
Ratio, proportion and rates of change · 3.3 Ratio, proportion and rates of change
Question and mark scheme from the AQA GCSE Mathematics examination, Paper 2 (Foundation), June 2025. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.