If rupee one produces rupees nine over a period of 40 years, find the rate of simple interest?
Choose the correct choice from the following options:  A) 22 1/7%  B) 22 7/2%  C) 29 1/2%  D) 22 1/2%  E) 22 1/3%
9 = (1*40*R)/100   R = 22 1/2 %   Answer: 22 1/2%
<result>D</result>
If rupee one produces rupees nine over a period of 40 years, find the rate of simple interest?