Year 11 - Maths
Checking and securing understanding of compound interest calculations
Iteration
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This pupil-friendly study guide includes a unit summary, clear notes, common mistakes, and quick questions with answers.
Unit Summary
In this unit, pupils continue to explore composite functions and develop understanding of iteration, building on their work on functions and proof.
Lesson Summary
You will learn to calculate compound interest.
Key Notes
- Compound interest can be thought of as a geometric sequence
- You can apply your knowledge of geometric sequences to solve algebraic compound interest problems
Vocabulary To Learn
- Simple interest: Interest is money added to savings or loans. Simple interest is always calculated on the original amount.
- Compound interest: Compound interest is calculated on the original amount and the interest accumulated over the previous period.
Common Mistakes To Avoid
- Pupils get confused between simple interest and compound interest. When presented with a compound interest problem the common error is for pupils to add the same constant amount.
3 Quick Questions (With Answers)
1. Solve this in steps: explain the method from this lesson and why each step matters.
Compound interest can be thought of as a geometric sequence. You can apply your knowledge of geometric sequences to solve algebraic compound interest problems.
2. Use this key word in a maths sentence and explain it clearly. 'Simple interest'
Interest is money added to savings or loans. Simple interest is always calculated on the original amount. Use this word when showing your method, then check your final answer is reasonable.
3. Spot and fix this common maths mistake.
Mistake: Pupils get confused between simple interest and compound interest. When presented with a compound interest problem the common error is for pupils to add the same constant amount. Correction: Visual representations are helpful here. The bar models in the first part of the lesson show how compound interest grows year on year. The graphical representation also demonstrates the fundamental difference between the two forms of interest.
More Lessons In This Unit
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