This exam tips covers Exam Success Strategies within Compound Measures for GCSE Mathematics. Revise Compound Measures in Number for GCSE Mathematics with 12 exam-style questions and 22 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 6 of 8 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
Exam Success Strategies
- Check your units: Always write the correct units with your answer
- Convert first: Get all measurements in the same units before calculating
- Use formula triangles: Draw them if you get stuck - cover what you want to find
- Average speed ≠ average of speeds: Always use total distance ÷ total time
- Show clear working: Even for simple calculations, show your method
- Reasonableness check: Does your answer make sense? A car speed of 200 m/s is clearly wrong!
Practice questions for Compound Measures
Which formula correctly gives speed in terms of distance and time?
A car travels 80 km at 40 km/h and then 80 km at 80 km/h. Explain why the average speed for the whole journey is NOT 60 km/h.
Quick recall flashcards
Convert 72 km/h to m/s
Divide by 3.6
72 ÷ 3.6 = 20 m/s
Check: 72 km/h means 72000 m per 3600 s
72000 ÷ 3600 = 20 m/s
Convert 25 m/s to km/h
Multiply by 3.6
25 × 3.6 = 90 km/h
Check: 25 m/s means 25 metres per second
25 × 3600 ÷ 1000 = 90 km/h