1.  Nitin borrowed some money at the rate of 6% p.a. for the first three years, 9% p.a. for the next five years and 13% p.a. for the period beyond eight years. If the total interest paid by him at the end of eleven years is ₹ 8160, how much money did he borrow ?
A. ₹ 8000
B. ₹ 10,000
C. ₹ 12,000
D. Data inadequate
E. None of these

Answer: Option A

Explanation:

Let the sum be Rs. X. Then,

(X x 6 x 3/100) + (X x 9 x 5 /100) + (X x 13 x 3/100)

 = 8160

<=> 18X + 45X + 39X = (8160 x 100)

<=> 102X = 816000

<=> X = 8000