BANK & INSURANCE (SIMPLE AND COMPOUND INTEREST) PART 1

Total Questions: 60

41. The difference between CI and SI on a certain sum of money at 15% per annum for 3 years is Rs.4394.25. Find the simple interest earned at the same rate of interest for 2 years on the same sum.

Correct Answer: (d) Rs.18600  
Solution:

Let the invested amount be Rs. P

D = [P² (300 + r)] / 100³

4394.25 = P × 15² × (300 + 15) / 1000000

P = Rs.62000

Simple interest = 62000 × 2 × 15/100 = Rs.18600

42. Kanish invested Rs.8000 in a simple interest scheme at the rate of R% per annum for 3 years. Kanika invested Rs.7500 in a simple interest scheme at the rate of (R + 5)% per annum for 2 years. If the ratio of the interest received by Kanish and Kanika is 6:5, then find the value of R?

Correct Answer: (d) 15  
Solution:

SI received by Kanish = 8000 × R × 3/100 = 240R
SI received by Kanika = 7500 × (R + 5) × 2/100
= 150R + 750

240R/(150R + 750) = 6/5
200R = 150R + 750
R = 15%

43. Leela invested Rs.x in a Simple interest scheme at the rate of R% per annum for 4 years. She received the amount of Rs.11109 for lending Rs.x for 2 years at 15% per annum Compound interest. If the simple interest she received after 4 years is Rs.6048, then find the value of R.

Correct Answer: (c) 18
Solution:

11109 = x × (1 + 15/100)²
11109 = x × 23/20 × 23/20
x = Rs 8400

6048 = 8400 × R × 4/100
R = 18%

44. Rs.7500 was invested for 3 years, partly in bank A at the rate of 12% S.I per annum and partly in bank B at the rate of 15% S.I per annum. Total interest received at the end of 3 years was Rs.3105. How much money was invested in bank B?

Correct Answer: (d) Rs.4500  
Solution:

Let the amount invested in bank B = x
The amount invested in Bank A = 7500 − x
(7500 − x) × 3 × 12/100 + x × 3 × 15/100 = 3105
x = 4500

45. The sum Rs.16000 invested equally at two different rates of interest and the difference between the simple interest is Rs.1200 for 3 years. Find the difference between rates of interest?

Correct Answer: (b) 5%  
Solution:8000 × R1 × 3/100 − 8000 × R2 × 3/100 = 1200
80 × 3(R1 − R2) = 1200
R1 − R2 = 5

46. The difference between the simple interest and compound interest for 3 years at 12% rate of interest per annum is Rs.1123.2. Find the sum?

Correct Answer: (d) Rs.25000  
Solution:The difference between the simple interest and compound interest for 3 years is,
Difference = [Sum × r² × (r + 300)]/100³
1123.2 = [Sum × 144 × 312]/100³
Sum = (1123.2 × 100 × 100 × 100)/(144 × 312)
Sum = Rs 25000

47. A sum of Rs.2900 amounts to Rs 3422 in 3 years at simple interest. If the interest rates were increased by 3% and rate of interest and sum invested is same, then find the total amount obtained?

Correct Answer: (b) Rs 3683  
Solution:

SI = 3422 − 2900 = 522
Rate = SI × 100/(P × time) = 522 × 100/(2900 × 3)
= 6%

New rate = 6 + 3 = 9%
New SI = 2900 × 9 × 3/100 = Rs. 783
Amount = P + SI = 2900 + 783 = 3683

48. Rahul invested Rs.x at the rate of 15% simple interest for 8 years and he also invested the same amount at the rate of 12% simple interest for same period. If the difference between the interest he received is Rs.4800, then find the value of x?

Correct Answer: (c) 20000
Solution:SI = P × N × R/100
x × 15 × 8/100 − x × 12 × 8/100 = 4800
24x = 48000
x = 20000

49. The interest earned on Rs.6800 at rate of x% compounded annually is Rs.1428 after 2 years. What would be the SI earned on the same sum at the rate of (x+5) % per annum after 3 years?

Correct Answer: (a) Rs.3060  
Solution:

According to the question,
6800 × ((x + 100)/100)((x + 100)/100) − 6800 = 1428

6800 × ((x + 100)/100)((x + 100)/100) = 8228
68 × ((x + 100)²)/100 = 8228

(x + 100)² = 12100
x + 100 = 110
x = 10

For SI, R = 10 + 5 = 15%
SI = 6800 × 15 × 3/100 = Rs. 3060

50. A invested Rs.4800 in scheme S which offers simple interest at x % per annum for 8 years. After 8 years, he received the interest amount is 300% more than that of the investment amount, then find the value of x?

Correct Answer: (c) 30  
Solution:SI = P × N × R/100
40/100 × 4800 = 4800 × 8 × x/100
x = 50%