Mr. Karan borrowed a certain amount at 6% per annum simple interest for 9 years. After 9 years, he returned Rs. 8510/-. Find out the amount that he borrowed. Choose one:  A) s . 5266  B) s . 5269  C) s . 5228  D) s . 5218  E) s . 5526

Rationale: "explanation : let us assume mr . karan borrowed amount is rs . a . ( the principal ) by formula of simple interest , s . i . = prt / 100 where p = the principal , r = rate of interest as a % , t = time in years s . i . = ( p * 6 * 9 ) / 100 = 54 p / 100 amount = principal + s . i . 8510 = p + ( 54 p / 100 ) 8510 = ( 100 p + 54 p ) / 100 8510 = 154 p / 100 p = ( 8510 * 100 ) / 154 = rs . 5525.974 answer : e"
Answer: E