Find the differnce between the compound interest and simple interest on Rs.40000 at 10% p.a. for 4 years? रु.40000 पर 4 वर्षों में 10% वार्षिक ब्याज की दर से साधारण ब्याज और चक्रवृद्धि ब्याज में अन्तर ज्ञात कीजिये |

SI = 40000 × 0.10 × 4 = Rs 16000. CI = 40000(1.10)^4 - 40000 = 40000 × 1.4641 - 40000 = Rs 18564 - 40000 = Rs 18564. CI - SI = 18564 - 16000 = Rs 2564. For quick verification: difference between CI and SI for 3 years at 10% is P(R^2)(R+3)%, and it increases each year. The difference grows with time due to the compounding effect on interest.