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

If a sum is invested in scheme B at C.I, then amount obtained after 2 year from this scheme is 1.44 times the sum invested. Rate of simple interest for scheme A is half of the rate of compound interest for scheme B. Find out the total interest earned when 8000 was invested in each scheme mentioned above for 2 years.

  1. 5120

  2. 5000

  3. 4800

  4. Can't be determined

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

Scheme B: A = 1.44P, so (1 + r/100)^2 = 1.44, 1 + r/100 = 1.2, r = 20%. Scheme A rate = 10%. Interest A = 8000 * 0.1 * 2 = 1600. Interest B = 8000 * (1.2^2 - 1) = 8000 * 0.44 = 3520. Total = 1600 + 3520 = 5120.

Multiple choice

The simple interest accrued, over a period of four years, on a certain sum would have been Rs.2000 more if the rate of interest had been 4% higher. Find the value of the sum.

  1. 20000

  2. 12000

  3. 10000

  4. 12500

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

The difference in interest is given by the formula (P * R2 * T / 100) - (P * R1 * T / 100) = 2000. Since the difference in rate (R2 - R1) is 4% and time T is 4 years, we have P * 4 * 4 / 100 = 2000. Solving for P gives P = 2000 * 100 / 16 = 12500.

Multiple choice

A part of Rs.8,250 is invested at a rate of 10% per annum and the remaining amount is invested at a rate of 20% per annum at simple interest. Both the amounts are invested for a period of two years and the interest earned on both the investments is same. How much amount was invested at the rate of 10%?

  1. 2750

  2. 4250

  3. 5250

  4. 5500

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

Let x be invested at 10%. Then (8250-x) is at 20%. Interest: (x * 0.1 * 2) = ((8250-x) * 0.2 * 2). 0.2x = 0.4(8250-x). 0.2x = 3300 - 0.4x. 0.6x = 3300. x = 5500.

Multiple choice

The difference between the simple and the compound interest on a sum for two years at a rate 10% p.a. is Rs.57.6. What is the one-fourth of the sum?

  1. 1450

  2. 1440

  3. 1420

  4. 1430

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

Volume = Volume of hemisphere + Volume of cone. Radius = 4.2. Height of hemisphere = 4.2. Height of cone = 10.2 - 4.2 = 6.0. Volume = (2/3 * pi * r^3) + (1/3 * pi * r^2 * h) = (1/3 * pi * r^2) * (2r + h) = (1/3 * 3.14 * 4.2^2) * (8.4 + 6) = 18.46 * 14.4 = 265.8. Matches option B.