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

Richard invested Rs. 13,900 by dividing the amount in two businesses - A and B. He invested some amount in business A at 14% p.a. simple interest and remaining amount in business B at 11% p.a. simple interest, respectively. If he earned Rs. 3,568 as the total interest after the end of 2 years, then find the amount of money he invested in business B.

  1. Rs. 5,100

  2. Rs. 5,400

  3. Rs. 5,500

  4. Rs. 5,600

  5. Rs. 5,700
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let x be the amount in B. Then (13900-x) is in A. Interest = (13900-x)*0.14*2 + x*0.11*2 = 3568. Solving for x: 3892 - 0.28x + 0.22x = 3568, so 0.06x = 324, x = 5400.

Multiple choice

Joe invests Rs. N in the equity share of XYZ Ltd. at 5% and Jessica invests Rs. (N - 100) in the mutual funds of XYZ Ltd. at 7%. After 4 years, the sum of the interests from both the investments is Rs. 4520. Find the value of N.

  1. Rs. 6005

  2. Rs. 8075

  3. Rs. 9475

  4. Rs. 10,475

  5. Rs. 10,805
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Interest from Joe = (N * 5 * 4) / 100 = 0.2N. Interest from Jessica = ((N-100) * 7 * 4) / 100 = 0.28(N-100). Total interest = 0.2N + 0.28N - 28 = 4520. 0.48N = 4548. N = 4548 / 0.48 = 9475.

Multiple choice

Raman took a loan of some amount and at the end of 2 years, he paid Rs. 54,121.6. The loan was taken at 4% rate of interest, compounded semi-annually. Find the principal amount.

  1. Rs. 40,000

  2. Rs. 46,000

  3. Rs. 50,000

  4. Rs. 42,000

  5. Rs. 44,000
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The formula for compound interest compounded semi-annually is A = P(1 + r/200)^(2n). Here, A = 54121.6, r = 4, and n = 2, so 54121.6 = P(1 + 2/100)^4 = P(1.02)^4. Calculating (1.02)^4 gives approximately 1.082432, and 54121.6 / 1.082432 = 50000.

Multiple choice

Rs. 2,02,800 is divided between Ram and Shyam such that the amount of interest Ram receives on his share in 3 years is the same as that Shyam receives on his share in 6 years. If it is simple interest at a rate of 4% per annum, then Ram's share is (in Rs.)

  1. 1,25,000

  2. 1,35,200

  3. 1,52,000

  4. 1,08,200
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let R be Ram's share, S be Shyam's share. R + S = 202800. Interest: (R * 4 * 3) / 100 = (S * 4 * 6) / 100. 12R = 24S, so R = 2S. 3S = 202800, S = 67600. R = 135200.

Multiple choice

Atul gave Rs. 12,000 to each of his two friends on interest for 2 years. For one, he calculated the interest at a rate of 6% (simple interest) and for the other, he calculated the interest at a rate of 5% compounded annually. What would be the difference between the amounts of interest paid by both friends?

  1. Rs. 48

  2. Rs. 82

  3. Rs. 122

  4. Rs. 210

  5. Rs. 225
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Simple interest for 2 years at 6% = 12,000 * 0.06 * 2 = 1440. Compound interest for 2 years at 5% = 12,000 * (1.05^2 - 1) = 12,000 * 0.1025 = 1230. The difference is 1440 - 1230 = 210.