This key facts covers Key Ratio Concepts within Ratio Basics for GCSE Mathematics. Revise Ratio Basics in Number for GCSE Mathematics with 12 exam-style questions and 22 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 3 of 15 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 3 of 15
Practice
12 questions
Recall
22 flashcards
Key Ratio Concepts
| Concept | Method | Example | Key Point |
|---|---|---|---|
| Simplifying | Divide by HCF | 6:8 = 3:4 | Find highest common factor |
| Sharing | Find total parts | Share £20 in 2:3 → 2+3=5 parts | Each part = total ÷ parts |
| Scaling | Multiply all parts | 2:5 scaled by 3 = 6:15 | Keep ratio the same |
| Three-way | a:b:c format | Red:Blue:Green = 2:3:5 | Total parts = a+b+c |
| Equivalent | Same when simplified | 4:6 = 2:3 = 6:9 | Multiply/divide both parts |
Keep building this topic
Read this section alongside the surrounding pages in Ratio Basics. That gives you the full topic sequence instead of a single isolated revision point.
Practice Questions for Ratio Basics
Write the ratio 12:18 in its simplest form.
Explain the difference between the ratio 3:5 and the ratio 5:3.
Quick Recall Flashcards
12 questions on Ratio Basics — practise free
Instant marking, adaptive difficulty, and 22 spaced repetition flashcards. Free until your GCSEs.
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