Concise Selina Solutions for Class 9 maths Chapter 3 Compound Interest (Using Formula)

Compound interest is the addition of interest to the principal sum of a loan or deposit, or in other words, interest on interest. It is the result of reinvesting interest, rather than paying it out, so that interest in the next period is then earned on the principal sum plus previously-accumulated interest. Compound interest is standard in finance and economics. Compound interest is calculated by multiplying the initial principal amount by one plus the annual interest rate raised to the number of compound periods minus one. The total initial amount of the loan is then subtracted from the resulting value.


Amount = Principal (1+Rate100) x time in years if compounded annually. Compound Interest formula in Maths: Compound Interest = Final amount - Original amount.