Module 1 · Arithmetic
Chapter 6: Simple Interest
Arithmetic
3 topics
What this chapter covers
The 3 topics below make up Simple Interest on the CAT. Click any topic to open its notes, examples and practice test.
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Formula Reference Sheet
This chapter
Core simple-interest relations
| Simple interest | SI = P × R × T / 100 |
|---|---|
| Amount (maturity value) | A = P + SI = P(1 + RT/100) |
| Principal from SI | P = 100 × SI / (R × T) |
| Rate from SI | R = 100 × SI / (P × T) |
| Time from SI | T = 100 × SI / (P × R) |
CAT power-tools
| Sum becomes n times in T years | R × T = (n − 1) × 100 |
|---|---|
| Yearly interest (a constant) | I per year = P × R / 100 |
| Equal annual instalment (loan, SI) | See instalment formula in SI Applications |
| Two amounts ⇒ principal & rate | Yearly interest = (A₂ − A₁)/(T₂ − T₁) |
| Average rate over split sums | Total SI / (Total P × Total T) × 100 |
CAT reference
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