Quantitative Aptitude

Simple and Compound Interest

3,394 Questions
All Simple interest and its inverse forms 768 Compound interest with annual compounding 742 Simple-interest growth and split sums 626 Difference between compound and simple interest 479 Half-yearly and quarterly compounding 252 Changing rates and fractional years 201 Installments (CI based) 190 Ratio of principal to interest 118 Population growth and depreciation 16

Simple and Compound Interest Questions

Multiple choice

Ravi bought a premium motorbike and paid 1 4 of its price through net banking and 1 3 in cash, agreeing to pay the remaining balance after two years with a 15% annual simple interest rate. If the total interest paid on the remaining amount was Rs. 45,000, then what was the original price of the bike?

  1. Rs. 3,85,000

  2. Rs. 3,66,000

  3. Rs. 3,36,000

  4. Rs. 3,60,000

  5. None of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Remaining amount = 1 - 1/4 - 1/3 = 5/12 of price. Interest = (5/12 * P) * 0.15 * 2 = 45000. (5/12 * P) * 0.3 = 45000. (5/12 * P) = 150000. P = 150000 * 12 / 5 = 360000.

Multiple choice

Rohit invests a total of ₹90,000 in three schemes A, B, and C for two years. The annual interest rates (compounded annually) are 10%, 8%, and 12%, respectively. The amount initially invested in scheme A is ₹25,000. The remaining amount is divided between schemes B and C such that the total interest from all three schemes during the first year is ₹9,500. If the interest is compounded annually, what is the total interest earned from all three schemes in the second year?

  1. ₹10,308

  2. ₹10,526

  3. ₹11,248

  4. ₹11,900
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Scheme A interest is 25000 * 0.10 = 2500. Total interest is 9500, so B + C interest is 7000. With 65000 remaining, let B = x, C = 65000 - x. 0.08x + 0.12(65000 - x) = 7000 leads to x = 20000 (Scheme B) and C = 45000. Second year interest is (25000 * 1.1 * 0.1) + (20000 * 1.08 * 0.08) + (45000 * 1.12 * 0.12) = 2750 + 1728 + 6048 = 10526.

Multiple choice

Ketty borrows Rs. 845 at the beginning of a year at a certain rate of simple interest. After 6 months, she borrows an additional Rs. 422.50 at twice the previous rate of interest. If the total interest on both borrowings at the end of the year is Rs. 53.50, what is the original rate of interest per annum?

  1. 4.5%

  2. 4.22%

  3. 3.16%

  4. 5%

  5. 5.25%
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Interest = (845 * r * 1) / 100 + (422.50 * 2r * 0.5) / 100 = 53.50. 8.45r + 4.225r = 53.50. 12.675r = 53.50. r = 4.22%.

Multiple choice

Mr. Jaipal has invested rs 8 lakhs in a bank at a rate of 10% compounded annually. He also gives a loan of 6 lakhs at simple interest but at same rate to one of his friend. He recieves both the amount at the end of 3 years. Find the difference (in lakhs) between both the amounts recieved by Mr. Jaipal at the end of 3 years ?

  1. 825,000

  2. 2,84,800

  3. 8,48,000

  4. 6,12,000

  5. 8,24,000
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Compound interest amount for 8 lakhs at 10% for 3 years is 8 * (1.1)^3 = 8 * 1.331 = 10.648 lakhs. Simple interest amount for 6 lakhs at 10% for 3 years is 6 + (6 * 0.1 * 3) = 6 + 1.8 = 7.8 lakhs. The difference is 10.648 - 7.8 = 2.848 lakhs, which is 2,84,800.

Multiple choice

Amalya invests certain sum at simple interest amounts to rs. 1290 in 3 yrs. and rs. 1410 in 7 yrs. On what principle and at what rate she earned the following amount

  1. 1200rs. , 5%.

  2. 1500rs. , 2.5%

  3. 1200rs. , 2.5%.

  4. 1500rs. , 3 %

  5. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

SI for 4 years (7-3) = 1410 - 1290 = 120. SI for 1 year = 30. SI for 3 years = 90. Principal = 1290 - 90 = 1200. Rate = (SI * 100) / (P * T) = (30 * 100) / (1200 * 1) = 2.5%.

Multiple choice

A sum of money was invested at simple interest for 4 years at an annual rate of 5%. The total interest earned was \$360. Quantity A The amount invested Quantity B \$1,200

  1. Quantity A is greater.

  2. Quantity B is greater.

  3. The two quantities are equal.

  4. The relationship cannot be determined from the information given.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Simple interest formula is I = P * r * t. Given I = 360, r = 0.05, and t = 4, we have 360 = P * 0.05 * 4, which is 360 = P * 0.20. Thus P = 360 / 0.20 = 1800. Since 1800 > 1200, Quantity A is greater.

Multiple choice

Divide Rs. 6,600 into two parts so that the simple interest on the first part for 5 years at 6% per annum is equal to the simple interest on the second part for 3 years at 12% per annum.

  1. (Rs. 4,000, Rs. 2,600)

  2. (Rs. 3,500, Rs. 3,100)

  3. (Rs. 3,600, Rs. 3,000)

  4. (Rs. 3,800, Rs. 2,800)

  5. NA
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let parts be x and y. x + y = 6600. (x * 5 * 6)/100 = (y * 3 * 12)/100 => 30x = 36y => x/y = 36/30 = 6/5. x = (6/11) * 6600 = 3600, y = 3000.

Multiple choice

Rate of Compound Interest? I: 1000 amounts to 1331. II: Period is 3 years. III: SI one year = CI first year.

  1. I & III sufficient

  2. I & II sufficient

  3. All 3 not sufficient

  4. I & II or III sufficient

  5. All 3 necessary
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Statement I (1000 to 1331) gives the ratio (1.331) for 3 years, allowing calculation of rate. Statement II (3 years) is needed to find the annual rate. Statement III is redundant as it is a property of compound interest.