In how many years Rs 200 will produce the same interest at 10% as Rs. 400 produce in 5 years at 12%  Choose the correct choice: A) 16 B) 13 C) 12 D) 14 E) 15

Rationale: "explanation : clue : firstly we need to calculate the si with prinical 400 , time 5 years and rate 12 % , it will be rs . 240 then we can get the time as time = ( 100 * 240 ) / ( 200 * 10 ) = 12 option c"
Answer: C