Playbook
Simple and Compound Interest
34 q · 15% HARD · about two a paper recently. Simple interest is nearly free; compound interest holds most of the HARD.
- Questions in the bank
- 34
- q/paper (21 papers)
- 1.62
- Tagged HARD
- 15%
- Subtopics
- 3
Strand: Quick-Win
When you’ll see it
Money lent or borrowed over time, simple or compound.
How this chapter is tested
34 questions, about two a paper on recent papers, at 15% HARD. Simple interest is nearly free; compound interest carries most of the HARD, usually through the difference between the two.
The sub-skills
The distinct skills inside the chapter, in the order to learn them.
Simple interest
SI = PRT/100.
Compound interest
A = P(1 + r/100)ⁿ; half-yearly halves the rate and doubles n.
CI − SI
For two years the difference is P(r/100)².
Traps to expect
Distractor shapes this chapter reuses. The Traps page covers the ones that cut across chapters.
Amount or interest
Options include both A and A − P.
Learn it before you drill it
This chapter has full teaching notes — foundations, worked examples, self-checks and a mastery check for each subtopic. Read the notes once, then drill subtopic by subtopic below.
Simple and Compound Interest notesDrill every Simple and Compound Interest question
34 questions from the bank, across 3 subtopics.
Drill one subtopic at a time
The 3 subtopics, in teaching order.
- Simple InterestDrill Simple Interest
- Compound InterestDrill Compound Interest
- Instalments and Difference of SI and CIDrill Instalments and Difference of SI and CI
Related playbooks
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