Reena took a loan of Rs. 1200 with simple interest for as many years as the rate of the interest. If she paid Rs. 432 as interest at the end of the period,what was the rate of interest ?
Pick one:  A) 3.6  B) 6  C) 18  D) Cannot be determined  E) None
Solution   Let rate = R% and time = R years.Then,   (1200xRxR/100)= 432 = 12R2= 432 = R2=36 =R = 6   Answer 6
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Reena took a loan of Rs. 1200 with simple interest for as many years as the rate of the interest. If she paid Rs. 432 as interest at the end of the period,what was the rate of interest ?