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

Rahul's annual starting salary is Rs. 2,40,000 and it increases by 20% each year. At the beginning of each year, he immediately invests 25% of that year's salary into the Future Wealth Scheme, which compounds annually at 15%. He makes one such beginning-of-year contribution in each of the first three years and leaves all contributions invested throughout. What is the total interest earned from the scheme by the end of the third year?

  1. Rs. 57,432.50

  2. Rs. 67,423.50

  3. Rs. 67,432.50

  4. Rs. 76,423.50
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Calculate the contribution for each year: Year 1: 60,000, Year 2: 72,000, Year 3: 86,400. Calculate the future value of each contribution after 3, 2, and 1 years respectively using compound interest formula A = P(1+r)^n. The total interest is the total future value minus the sum of contributions (218,400).

Multiple choice

Statement I: A principal amount of ₹5,000 doubles itself under simple interest in a certain number of years. Statement II: The total simple interest earned on the principal amount in 8 years is equal to the principal amount itself.

  1. Statement I alone is sufficient

  2. Statement II alone is sufficient

  3. Both Statements I and II together are necessary

  4. Either Statement I alone or Statement II alone is sufficient

  5. Both Statements I and II together are not sufficient
Reveal answer Fill a bubble to check yourself
D Correct answer
Multiple choice

A principal sum of money yields an absolute simple interest amount of Rs. 4,320 at the end of 4 years at a flat rate of 9% per annum. What would be the compound interest generated by the same principal sum at the end of 2 years at a rate of 10% per annum, compounded annually?

  1. Rs 2,400

  2. Rs 2,520

  3. Rs. 2,640

  4. Rs. 2,720

  5. Rs. 2,310
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Simple interest = P*r*t/100 -> 4320 = P*9*4/100 -> 4320 = 0.36P -> P = 12000. Compound interest on 12000 for 2 years at 10%: 12000 * (1.1^2 - 1) = 12000 * 0.21 = 2520.

Multiple choice

The simple interest on a certain deposit at 4.5% per annum is Rs. 202.50 in one year. How much additional interest will be earned in one year on the same deposit at a rate of 5% per annum?

  1. Rs. 20.25

  2. Rs. 22.50

  3. Rs. 25

  4. Rs. 42.75

  5. Rs. 42.25
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Simple interest is proportional to the rate. If 4.5% yields Rs. 202.50, then 1% yields 202.50 / 4.5 = Rs. 45. The interest at 5% is 5 * 45 = Rs. 225, so the additional interest is 225 - 202.50 = Rs. 22.50.

Multiple choice

Each of the questions given below consists of a question and two statements numbered I and II given below it. You have to decide whether the data provided in the statements sufficient to answer the question. Give answer (a) If the data in statement I alone are sufficient to answer the question, while the data in statement II alone are not sufficient to answer the question (b) If the data in statement II alone are sufficient to answer the question, while the data in statement I alone are not sufficient to answer the question (c) If the data in statement I alone or in statement II alone are sufficient to answer the question (d) If the data in both the statements I and II are not sufficient to answer the question (e) If the data in both the statements I and II together are necessary to answer the questionWhat is the rate of interest p.c.p.a.? I. An amount of Rs. 14350 gives a simple interest of Rs. 11480 in 4 yr. II. The amount doubles itself in 5 yr with simple interest.

  1. a

  2. b

  3. c

  4. d

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

Statement I: Interest = 11480, Principal = 14350, Time = 4. R = (100 * I) / (P * T) = (100 * 11480) / (14350 * 4) = 20%. Statement II: Amount doubles in 5 years means interest equals principal, so 100% interest in 5 years, meaning 20% per year. Both statements independently provide the rate.

Multiple choice

Directions: Each of the questions below consists of a question and three statements numbered I, II and III given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. Read all the statements and give answer: Find the rate of simple interest per annum. I. Meetu borrowed Rs 9000 from Sneha for two years on simple interest. II. Meetu returned Rs 11700 to Sneha at the end of two years and settled the loan. III. A sum of money becomes double in 20/3 years on simple interest.

  1. The data in statements I alone is sufficient to answer the question, while the data in statement II and II is not sufficient to answer the question.

  2. The data in statements II alone is sufficient to answer the question, while the data in statement II and III is not sufficient to answer the question.

  3. The data in statements I and II together or in statement III alone is sufficient to answer the question.

  4. The data in all the statements I, II and III is not sufficient to answer the question.

  5. The data in all the statements I, II and III together is necessary to answer the question.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Statements I and II give a principal of Rs. 9000, interest of Rs. 2700, and time of 2 years, which determines the rate as 15% per annum. Statement III alone also gives the rate because doubling in 20/3 years means the simple-interest rate is 100/(20/3) = 15%.

Multiple choice

Directions: Each of the questions below consists of a question and two statements numbered I and II given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. Read both the statements and give answer: Find the rate of interest. I. A sum of money becomes double of itself at simple interest in 12.5 years. II. 5000 becomes 5832 in 2 years at compound interest.

  1. The data in statements I alone is sufficient to answer the question, while the data in statement II alone is not sufficient to answer the question.

  2. The data in statements II alone is sufficient to answer the question, while the data in statement I alone is not sufficient to answer the question.

  3. The data in statements I alone or in statement II alone is sufficient to answer the question.

  4. The data in both the statements I and II is not sufficient to answer the question.

  5. The data in both the statements I and II together is necessary to answer the question.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Statement I: A = 2P, so P(1 + r/100 * 12.5) = 2P, which allows solving for r. Statement II: 5832 = 5000(1 + r/100)^2, which also allows solving for r. Both are sufficient independently.

Multiple choice

Directions: This data sufficiency problem consists of a question and two statements labelled (1) and (2). You have to decide whether the data given in the statements is sufficient for answering the question. Find the rate of interest per annum. (1) The amount invested by Payal is Rs. 8,000 and becomes Rs. 11,520 in 2 years at compound interest. (2) The amount invested by Payal is Rs. 8,000 and the difference between CI and SI at the same rate of interest in two years is Rs. 320.

  1. Statement (1) alone is sufficient, but statement (2) alone is not sufficient.

  2. Statement (2) alone is sufficient, but statement (1) alone is not sufficient.

  3. Both statements (1) and (2) together are sufficient, but neither of them alone is sufficient.

  4. Both the statements alone are sufficient.

  5. Both statements (1) and (2) together are not sufficient.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Statement 1: 11520 = 8000(1 + R/100)^2 leads to (1 + R/100)^2 = 1.44, so 1 + R/100 = 1.2, R = 20%. Statement 2: 320 = 8000(R/100)^2 leads to (R/100)^2 = 320/8000 = 0.04, R = 20%. Both are sufficient alone.