Rs. 16820 is divided between two brothers of age 27 years and 25 years. They invested their money at 5% per annum compound interest in such a way that both will receive equal money at the age of 40 years. Find the share of elder brother?

Let the shares be A (27-year-old) and B (25-year-old), with A + B = 16820. At 5% compound interest, after (40-27)=13 years A becomes A(1.05)^13, and after (40-25)=15 years B becomes B(1.05)^15. For equal amounts at age 40: A(1.05)^13 = B(1.05)^15, giving A/B = (1.05)^2 = 1.1025. Solving A + B = 16820 and A = 1.1025B gives 2.1025B = 16820, B = 8000, A = 8820. The elder brother (27-year-old) gets 8820. Option B is correct.