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THE VISUAL LEARNING STUDIO
See the idea. Understand the connection.
35 visual explanations across 29 chapters, with topic maps throughout the library.
The chapter index will grow as additional notes are prepared. Chapters shown here are a learning collection, not a claim that the entire exam syllabus is complete.
SEE IT. CONNECT IT. EXPLAIN IT.
Understand the chapter visually
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Study the expanded notes and the credited detailed textbook lessons. The current chapter index covers core topics; it is not a claim of exhaustive coverage of every examination syllabus. Check the official syllabus and primary references.
Simple and Compound Interest — lesson overview
Simple interest
For principal P, annual rate r% and time t years under a simple-interest convention, interest I=Prt/100.
Interest is calculated on the original principal throughout. Total amount is P+I, not merely the interest figure.
Rate and time units must match; six months is half a year when using an annual simple-interest rate.
Compound interest
With annual compounding, amount A=P(1+r/100)ⁿ for n years under the stated fixed-rate assumptions.
Compound interest includes growth on earlier interest. A different compounding frequency changes the periodic rate and number of periods.
At 10% annually, ₹1,000 becomes ₹1,210 after two years; interest is ₹210, compared with ₹200 under simple interest.
Comparison and interpretation
For the same positive rate, principal and two-year period with annual compounding, the extra compound interest over simple interest is P(r/100)².
Real financial products can have fees, taxes and different conventions; an aptitude formula is a specified mathematical model.
An advertised annual rate should not be compared mechanically with an unrelated periodic rate without converting the assumptions.
