Reena took a loan of $. 1200 with simple interest for as many years as the rate of interest. If she paid $ 108 as interest at the end of the loan period, what was the rate of interest?
Choose the correct choice from the following options:	A) 3.6	B) 6	C) 18	D) 3	E) none of these

Rationale: let rate = r % and time = r years . then , 1200 x r x r / 100 = 108 12 r 2 = 108 r 2 = 9 r = 3 . answer : d
Answer: D