Use some thinking to answer the following question. If rupee one produces rupees nine over a period of 40 years, find the rate of simple interest?
Options:
(A) 22 1/8 %
(B) 22 3/2 %
(C) 28 1/2 %
(D) 22 1/2 %
(E) 32 1/2 %
9 = (1*40*R)/100
R = 22 1/2 % So the final answer is (D).