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

Directions: The given table shows the values of interest on deposits for a year. Deposit (in Rs.) 1000 2000 3000 4000 5000 Simple Interest (in Rs.) 80 160 240 320 400 To get an interest of Rs. 280 per year, how much money should be deposited?

  1. Rs. 4000

  2. Rs. 3500

  3. Rs. 3250

  4. Rs. 3000
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The simple interest is proportional to the deposit amount. From the table, 1000 Rs gives 80 Rs interest, meaning the interest rate is 8 percent per year. To earn 280 Rs interest, the deposit must be 280 / 0.08 = 3500 Rs.

Multiple choice

Directions: The following table shows the interests on different deposits for a year. Deposit (in Rs.) 1000 2000 3000 4000 5000 Simple Interest (in Rs.) 80 160 240 320 400 From the table, what is the interest on Rs. 2500 for a year?

  1. Rs. 160

  2. Rs. 180

  3. Rs. 200

  4. Rs. 240
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The interest is directly proportional to the deposit. Interest = 80 for 1000, so rate = 80/1000 = 0.08. For 2500, interest = 2500 * 0.08 = 200.

Multiple choice

The given table shows interest earned on deposits for a year: Deposit (in Rs.) 1000 2000 3000 4000 5000 Simple Interest (in Rs.) 80 160 240 320 400 What type of graph will we get for the above given table?

  1. Non-linear graph

  2. Linear graph

  3. Pie graph

  4. Histogram
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The ratio of interest to deposit is constant (80/1000 = 0.08). Since the relationship is proportional (y = 0.08x), the graph is a straight line passing through the origin.

Multiple choice

Kunal borrowed Rs. P at a compound interest of 20% p.a. for 2 years. Amount payable after 2 years was Rs. 6336. What was the value of P? কুনাল চক্রবৃদ্ধি সুদে 20% হারে 2 বছরের জন্য P টাকা ধার নিয়েছিল। 2 বছরপর প্রদেয় অর্থের পরিমাণ ছিল 6336, তাহলে P এর মান কত ছিল?

  1. Rs. 4400

  2. Rs. 5000

  3. Rs. 4750

  4. Rs. 4500
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Amount = P * (1 + r/100)^n. 6336 = P * (1 + 20/100)^2 = P * (1.2)^2 = P * 1.44. P = 6336 / 1.44 = 4400.

Multiple choice

Nishit deposited a certain sum of money in a post office at 10% p.a. for 4 years and deposited an equal amount in a fixed deposit in a bank for 5½ years at 11% p.a. If the difference in the interest from the two sources is Rs. 563.75, find the sum deposited. মেসি তো নিশিত একটি পোস্ট অফিসে কিছু নির্দিষ্ট পরিমাণ অর্থ 10% বার্ষিক হারে 4 বছরের জন্য এবং সমপরিমাণ অর্থ 11% বার্ষিক হারে 5.5 বছরের জন্য একটি ব্যাংকে জমা রাখে।যদি দুটি উৎস থেকে প্রাপ্ত সুদ এর মধ্যে পার্থক্য 563.75 হয় ,তাহলে সে কত টাকা জমা রেখেছিল?

  1. Rs. 14083.75

  2. Rs. 10250

  3. Rs. 2550

  4. Rs. 2750
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let the sum be P. The interest from the first source is P * 0.10 * 4 = 0.4P. The interest from the second source is P * 0.11 * 5.5 = 0.605P. The difference is 0.605P - 0.4P = 0.205P = 563.75. Solving for P gives P = 563.75 / 0.205 = 2750.

Multiple choice

X borrowed Rs. 10,000/- from two different banks. For one loan, he paid 12% and for other 14% per annum. After one year, he paid Rs.1280/- as interest. How much did he borrow at the rate of 14%?

  1. 4000

  2. 6000

  3. 5000

  4. 4500
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Let x be the amount at 14% and (10000-x) be the amount at 12%. The equation is 0.14x + 0.12(10000-x) = 1280, which simplifies to 0.02x + 1200 = 1280. Solving for x gives 0.02x = 80, so x = 4000.

Multiple choice

With the given rate of simple interest, the ratio of principle and amount for a certain period of time is 4:5. After 3 years, with the same rate of interest, the ratio of the principle and amount becomes 5:7. Find the rate of interest.

  1. 4%

  2. 6%

  3. 5%

  4. 7%
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let P be principal and R be rate. Initially P/A = 4/5, so interest for some time T is P/4. After 3 years, P/A = 5/7. By setting up the simple interest equations (I = PRT/100), one can solve for the rate. The calculation yields 5%.

Multiple choice

Directions: The following question is accompanied by statements A, B and C. You have to determine which of the statements is/are sufficient/necessary to answer the question. Find the principle amount that Romi will have to pay. A. There is 65% increase in an amount in 5 years at simple interest. B. The rate of interest before 65% increase was 10% p.a. C. After 3 years, compound interest at the same rate will be Rs. 3972.

  1. Only C is sufficient.

  2. A and C together are sufficient.

  3. All together are sufficient.

  4. Either B or C is sufficient.

  5. Only A is sufficient.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Statement A gives the simple interest rate as 65%/5 = 13% per year. Using this rate in statement C, the compound interest for 3 years determines the principal amount, so A and C together are sufficient.

Multiple choice

Gopal invested a certain sum of money that becomes Rs. 11,110 after 4 years and Rs. 16,665 after 8 years on compound interest. Find the sum invested by Gopal.

  1. Rs. 4,440.56

  2. Rs. 7,406.67

  3. Rs. 7,556.67

  4. Rs. 11,110.67

  5. Rs. 5,200.56
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In compound interest, the amount grows in geometric progression. If A1 = P(1+r)^4 = 11110 and A2 = P(1+r)^8 = 16665, then (1+r)^4 = 16665 / 11110 = 1.5. Thus, P = 11110 / 1.5 = 7406.67.

Multiple choice

Nitin invested in two different schemes: Y and Z. He invested a total sum of Rs. 16,000. He invested part of the sum at 15% per annum in Y and the rest at 12% per annum in Z. He earned a total simple interest of Rs. 4000 in 2 years. What was the approximate amount (in Rs.) he invested in scheme Y?

  1. 3197

  2. 2537

  3. 2667

  4. 2853

  5. 2601
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let x be the amount in Y. Interest = (x * 0.15 * 2) + ((16000 - x) * 0.12 * 2) = 4000. 0.3x + 0.24(16000 - x) = 4000. 0.3x + 3840 - 0.24x = 4000. 0.06x = 160. x = 160 / 0.06 = 2666.67.

Multiple choice

Direction : Study the following questions carefully and choose the right answer. Rs. 160000 is divided into two equal parts. One part is invested in a scheme which gives 12% interest compounded annually for two years. The other part is invested in a scheme offering simple interest of 13% for 2 years. What is the difference between the interest earned on the two schemes?

  1. Rs. 512

  2. Rs. 426

  3. Rs. 448

  4. Rs. 568

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

Part 1 (CI): 80000 * (1.12^2 - 1) = 80000 * 0.2544 = 20352. Part 2 (SI): 80000 * 0.13 * 2 = 20800. Difference = 20800 - 20352 = 448.

Multiple choice

Direction : Study the following questions carefully and choose the right answer. If the compound interest on certain sum at 4% for 2 years is Rs. 2448. Find the simple interest on the same sum at the same rate for the same period.

  1. 2500

  2. 2400

  3. 2436

  4. 2420

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

CI = P((1+r/100)^n - 1). 2448 = P((1.04)^2 - 1) = P(1.0816 - 1) = P(0.0816). P = 2448 / 0.0816 = 30000. SI = P * r * t / 100 = 30000 * 4 * 2 / 100 = 2400.