Simple Interest Formula
SI = P × R × T / 100 where P = Principal, R = Annual Rate %, T = Time in years. Total Amount = P + SI.
Example: ₹10,000 at 10% for 2 years → SI = 10,000 × 10 × 2 / 100 = ₹2,000. Total = ₹12,000.
SI vs Compound Interest: Simple interest doesn't compound — interest is not earned on interest. CI always gives higher returns for the same rate and period.