What sum of money put at C.I amounts in 2 years to Rs.8820 and in 3 years to Rs.9261?  Choose the correct choice from the following answers.
A) rs . 8000 B) rs . 8400 C) rs . 7500 D) rs . 7800 E) none of these

Rationale: "explanation : 8820 - - - - 441 100 - - - - ? = > 5 % x * 105 / 100 * 105 / 100 = 8820 x * 1.1025 = 8820 x = 8820 / 1.1025 = > 8000 answer is a"
Answer: A