Simple Interest problems
- 1. A certain sum of money at simple interest amounts to Rs. 1260 in 2 years and to Rs. 1350 in 5 years. The rate per cent per annum is?
Options- A. 2.5%
- B. 3.75%
- C. 5%
- D. 7.5% Discuss
Correct Answer: 2.5%
Explanation:
S.I for 3 years = Rs. (1350 - 1260) = Rs. 90
S.I for 2 years = Rs.(90/3) x 2 = Rs . 60
? Sum = Rs. (1260 - 60) = Rs. 1200
? Rate = (100 x SI) / (P x T) = (100 x 60) / (1200 x 2) = 2.5%
- 2. A lent Rs. 600 to B for 2 years and Rs. 150 to C for 4 years and received altogether from both Rs. 90 as simple interest. The rate of interest is?
Options- A. 4%
- B. 5%
- C. 10%
- D. 12% Discuss
Correct Answer: 5%
Explanation:
Let rate = R% per annum.
Then, [(600 x R x 2)/ 100 ] + [(150 x R x 4 ) / 100] = 90
? 18R = 90
? R = 5%
- 3. Rs. 800 amounts to Rs. 920 in 3 years at simple interest. If the interest rate is increased by 3% It would amount to how much?
Options- A. Rs. 1056
- B. Rs. 1112
- C. Rs. 1182
- D. Rs. 992 Discuss
Correct Answer: Rs. 992
Explanation:
Principal = Rs. 800
S.I. = Rs. (920 - 800) = Rs. 120
and Time = 3 years
? Original rate = (100 x SI) / (P x T) = (100 x 120) / ( 800 x 3) = 5%
New rate = 8%
Now, S.I . = Rs.(800 x 8 x 3) /100 = Rs. 192
? Amount = Rs. (800 + 192)
= Rs. 992
- 4. The simple interest on a sum of money at 8% per annum for 6 years is half the sum. The sum is?
Options- A. Rs. 4800
- B. Rs. 6000
- C. Rs. 8000
- D. Data inadequate Discuss
Correct Answer: Data inadequate
Explanation:
Let, Sum = P
Then S.I = P/2
Rate = 8%
and Time = 6 years
But P/2 = (P x 8 x 6) /100 (Not possible )
Thus, data is inadequate.
- 5. If the interest on Rs. 1200 be more than the interest on Rs. 1000 by Rs. 50 in 3 years, the rate per cent is?
Options- A. 101/3%
- B. 62/3%
- C. 81/3%
- D. 92/3% Discuss
Correct Answer: 81/3%
Explanation:
Let rate = R% per annum. Then,
(1200 x R x 3)/100 - (1000 x R x 3)/100 = 50
? 6R = 50
? R = 81/3
? Rate = 81/3% per annum
- 6. In how many years will a sum of money double itself at 12% per annum?
Options- A. 6 years 9 months
- B. 8 years 4 months
- C. 7 years 6 months
- D. 8 years 6 months Discuss
Correct Answer: 8 years 4 months
Explanation:
Let principal = P.
Then, S.I = P,
Rate (R) = 12%
Time = (100 x SI) / (R x P) = (100 x P) / (P x 12) years
= 25/3 years
= 8 years 4 months
- 7. A sum was put at simple interest at a certain rate for 2 years. Had it been put at 1% higher rate, it would have fetched Rs. 24 more, The sum is?
Options- A. Rs. 600
- B. Rs. 800
- C. Rs. 1200
- D. Rs. 480 Discuss
Correct Answer: Rs. 1200
Explanation:
Let sum = P and original rate = R% per annum
Then, [(P x (R + 1) x 2)/100] - [(P x R x 2)/100] = 24
? P = 1200
- 8. A sum money becomes (8/5) of itself in 5 years at a certain rate of interest . The rate percent per annum is?
Options- A. 5%
- B. 8%
- C. 10%
- D. 12% Discuss
Correct Answer: 12%
Explanation:
Let sum = Rs. P.
Then amount = Rs. (8P/5)
? S.I = Rs. (8P/5 - P ) = Rs.(3P/5)
? Required rate = (100 x SI) / (P x T)
= [(100 x 3P/5) / (P x 5)]% = 12%
- 9. The difference between the interest received from two different bank on Rs. 500 for 2 year is Rs. 2.50. The difference between their rates is?
Options- A. 1%
- B. 0.5%
- C. 2.5%
- D. 0.25% Discuss
Correct Answer: 0.25%
Explanation:
Let the rates be R1% and R2%.
Then, (500 x R1 x 2)/ 100 - (500 x R2 x 2)/ 100 = 2.5
? 10(R1 - R2) = 2.5
? Req difference = R1 - R2 = 0.25%
- 10. A certain sum of money at simple interest amounts to Rs. 1012 in 2 1/ 2 years and to Rs. 1067.20 in 4 years. The rate of interest per annum is?
Options- A. 2.5%
- B. 3%
- C. 4%
- D. 5% Discuss
Correct Answer: 4%
Explanation:
? S.I. for 3/2 years = Rs. (1067.20 - 1012) = Rs. 55.20
? S.I. for 5/2 years = Rs. 55.20 x (2/3) x (5/2) = 92
? Sum = Rs. (1012 - 92) = Rs.920
Hence, Rate = (100 x SI)/(P x T) = (100 x 92) / (920 x 5/2 ) = 4%
More in Aptitude:
Programming
Copyright ©CuriousTab. All rights reserved.