A six-year period results in a 60 percent rise in a sum at simple interest. After three years at the same rate, what would the compound interest on Rs. 12,000 be?
A. Rs. 2160
B. Rs. 3120
C. Rs. 3972
D. Rs. 6240
Answer:C
A six-year period results in a 60 percent rise in a sum at simple interest. After three years at the same rate, what would the compound interest on Rs. 12,000 be?
A. Rs. 2160 B. Rs. 3120 C. Rs. 3972 D. Rs. 6240
Explanation: Let P be equal to Rs. 100. Then T = 6 years and S.I. Rs. 60.R = 100 x 60 /100 x 6 = 10% p.a. R = 100 x 60 /100 x 6 = 10% p.a.P is now equal to Rs. 12000. T equals three years, and R equals ten percent every year.C.I. = Rs.12000 multiplied by (1 + 10/100) to the third power - 1= Rs.12000 x 331 /1000=The number 3972.