If the simple interest on a sum of money for 5 years at 9% per annum is Rs. 800, what is the compound interest on the same sum at the rate and for the same time? Choices:
A) Rs. 947.55  B) Rs. 957.55  C) Rs. 857.55  D) Rs. 657.55  E) Rs. 357.55
Sum = (800 * 100) / (5 * 9) = Rs. 1,777.78   C.I. on Rs. Rs. 1,777.78 for 5 years at 9% = Rs. 2,735.33.   = Rs. 2,735.33 - 1,777.78 = Rs. 957.55   ANSWER:Rs. 957.55
<result>B</result>
If the simple interest on a sum of money for 5 years at 9% per annum is Rs. 800, what is the compound interest on the same sum at the rate and for the same time?