Simple interest
- Find one year of interest.
- Multiply by the number of years.
- Add it to the original if the final balance is needed.
Answer: £500 at 4% for 2 years earns £40
⚖️ Ratio, Proportion & Rates
Simple interest
Learn simple interest with a GCSE-style explanation, help guide, worked example, practice question and flashcards.
Global XP
Level 10 / 100 XP
1. Explanation
Key idea
- Simple interest is part of measures & money and appears often in KS3–GCSE maths.
- Simple interest is calculated only on the original amount.
- Use the worked model, help guide, interactive question and flashcards to practise simple interest until the steps feel automatic.
Real-life examples
- Shopping, sport, travel, science, design and everyday decisions all use this skill.
2. Visual
Simple interest learning map
Understand the key idea → follow the help guide → practise a question → check your method → build speed with flashcards.
3. Help guide
How to tackle Simple interest
- Learn the rule: Simple interest is calculated only on the original amount.
- Worked model: Find one year of interest. Multiply by the number of years. Add it to the original if the final balance is needed.
- Try the interactive question without looking at the answer first.
- Use the flashcards to test the rule, the method and a common check.
4. Worked examples
Step-by-step working
5. Interactive questions
Try it yourself
Find simple interest on £200 at 5% for 3 years.
6. Flashcards
Master quick recall
Flip each card, then choose whether you know it or need more practice.
0 mastered
FrontRule for Simple interest
BackSimple interest is calculated only on the original amount.
FrontExample answer: Find simple interest on £200 at 5% for 3 years.
Back5% of £200 is £10 per year. For 3 years: £10 × 3 = £30.
FrontCommon check for Simple interest
BackCheck units/notation, compare with an estimate, and make sure the answer matches the question.
7. Finish
Complete this topic
When you have read the examples, tried the question and reviewed flashcards, claim your topic completion XP.