AQA GCSE Mathematics Paper 2 (Foundation), June 2025: Question 8
4 marks · Easy difficulty · Short Answer
Convert between units of time (hours to minutes), mass (grams to kilograms), and distance (kilometres to miles using a given conversion rate).
Practise this questionQuestion
Mark scheme
Show the mark scheme
How to answer it
Converting Units of Time, Mass, and Distance
📌 What This Question Tests
This question assesses your ability to convert between different standard metric and imperial units across three everyday contexts:
- Time: Converting mixed hours to minutes using the fact that 1 hour = 60 minutes.
- Metric Mass: Converting grams to kilograms using the base prefix kilo = 1000.
- Proportional Distance: Using a given ratio conversion (8 kilometres = 5 miles) to convert between metric and imperial distances.
Question 8 (a) • 1 Mark
Convert 3 ½ hours to minutes
Topic: Units of Time
📐 Step-by-Step Calculation
- Identify the conversion factor: 1 hour = 60 minutes
- Convert the whole hours: 3 × 60 = 180 minutes
- Convert the half hour: ½ × 60 = 30 minutes
- Add them together: 180 + 30 = 210 minutes
✅ Correct Answer
210 minutes
Mark Scheme: B1 for fully correct value of 210.
💡 Key Knowledge
- Time does not use base 10 (decimals)! Always use 60 minutes = 1 hour .
- Alternative method: Convert to an improper fraction or decimal first:
3.5 × 60 = 210
❌ Common Errors
- Treating time as base 100: Thinking 3 ½ hours means 350 minutes or writing 3.5 × 100.
- Mixing up operations: Dividing by 60 instead of multiplying.
Question 8 (b) • 1 Mark
Convert 1400 grams to kilograms
Topic: Metric Mass
📐 Step-by-Step Calculation
- Recall the prefix kilo- means 1000: 1 kg = 1000 g
- Converting from a smaller unit (g) to a larger unit (kg) requires division:
- Calculate: 1400 ÷ 1000 = 1.4 kg
✅ Correct Answer
1.4 kg
Mark Scheme: B1 for 1.4 (Additional Guidance: condone trailing zeros such as 1.40).
🧠 Exam Technique
- To divide by 1000, shift the digits 3 places to the right relative to the decimal point: 1400.0 → 1.4
- Sense check: A kilogram is heavier than a gram, so the number of kilograms must be smaller than the number of grams.
❌ Common Errors
- Multiplying instead of dividing: Giving an unreasonable answer like 1 400 000 kg.
- Wrong power of 10: Dividing by 100 instead of 1000 to get 14 kg.
Question 8 (c) • 2 Marks
Convert 32 kilometres to miles (using 8 km = 5 miles)
Topic: Proportion & Unit Conversions
📐 Step-by-Step Calculation
- Find the scale factor: How many groups of 8 km fit into 32 km?
32 ÷ 8 = 4 - Scale up the miles: Multiply the number of miles per 8 km by the scale factor:
4 × 5 = 20 miles
✅ Correct Answer
20 miles
Mark Scheme:
• M1: For 32 ÷ 8 (or 4), OR 32 × 5 (or 160), OR 5 ÷ 8 (0.625), OR listing multiples 8, 16, 24, 32 .
• A1: Fully correct answer of 20 .
• M1: For 32 ÷ 8 (or 4), OR 32 × 5 (or 160), OR 5 ÷ 8 (0.625), OR listing multiples 8, 16, 24, 32 .
• A1: Fully correct answer of 20 .
🧠 Alternative Method (Unitary Method)
- Find 1 km in miles: 5 ÷ 8 = 0.625 miles
- Multiply by 32 km: 32 × 0.625 = 20 miles
- Top Tip: The scale factor method ( 32 ÷ 8 = 4 ) is usually much faster and avoids decimals!
❌ Common Errors
- Flipping the ratio: Multiplying 32 by 8 and dividing by 5 ( 51.2 ) — remember miles are longer than kilometres, so the number of miles must be smaller than 32.
- Stopping halfway: Writing 4 as the final answer after calculating 32 ÷ 8 , forgetting to multiply by 5.
Topics
Number · Ratio, proportion and rates of change · 3.1.3 Measures and accuracy · 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.