A sum of Rs. 725 is lent at a fixed rate of interest at the start of the year. After 8 months, a further Rs. 362.50 is lent, but at a rate twice as high as before. Interest from both loans totals Rs. 33.50 at the end of the year. What was the original interest rate?
A. 3.6%
B. 4.5%
C. 5%
D. None of these
Answer:D
A sum of Rs. 725 is lent at a fixed rate of interest at the start of the year. After 8 months, a further Rs. 362.50 is lent, but at a rate twice as high as before. Interest from both loans totals Rs. 33.50 at the end of the year. What was the original interest rate?
A. 3.6% B. 4.5% C. 5% D. None of these
Explanation: Let's say the initial rate was R percent. Then the new rate is equal to (2R) percent. Note that the original fee is for 1 year(s); the new rate is just for 4 months, or a year (s). 33.50 = 725 x R x 1 /100 + 362.50 x 2R x 1/100 X 3,(725 + 2175) R = 33.50 x 100 x 3 (2175 + 725) R = 33.50 x R is equal to 10050 ,2900 R = 10050 = 3.46 %