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

Under a new scheme, a bank offers an interest of 30% per annum compounded annually. Suraj deposits Rs. 10,000 under this new scheme and at the end of the tenure receives Rs. 28,561. What is the tenure of the scheme that Suraj has chosen?

  1. 2 years

  2. 3.5 years

  3. 4 years

  4. 4.5 years

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

The formula for compound interest is A = P(1 + r/100)^n. Substituting the values, 28561 = 10000(1 + 0.30)^n, which simplifies to 2.8561 = (1.3)^n. Since 1.3^4 = 2.8561, the tenure is 4 years.

Multiple choice

Ruby has a certain amount of money which amounts to Rs. 98,000 in 2 years and Rs. 1,28,000 in 4 years when compounded yearly. Find the rate of interest.

  1. 25%

  2. 20.2%

  3. 18.82%

  4. 14.29%

  5. 13%
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let P be the principal and r be the rate. We have P(1+r)^2 = 98000 and P(1+r)^4 = 128000. Dividing the second by the first gives (1+r)^2 = 128000/98000 = 128/98 = 64/49. Thus, 1+r = 8/7, so r = 1/7, which is approximately 14.285%.

Multiple choice

Simran lent Rs. 8000 to Piyush for 4 years and Rs. 4000 to Ishmeet for 2 years on Simple Interest at same rate of interest and received Rs. 2640 in total from both the persons as interest. What is the rate of interest per annum?

  1. 5.4%

  2. 5.6%

  3. 6.6 %

  4. 12.5%

  5. 13.6%
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let R be the rate. Simple interest = (P * R * T) / 100. (8000 * R * 4)/100 + (4000 * R * 2)/100 = 2640. 320R + 80R = 2640. 400R = 2640. R = 2640 / 400 = 6.6%.

Multiple choice

Pooja has a certain sum of money. She deposited Rs. 1120 with bank A at simple interest for 4 years at 5% per annum. She deposited the remaining with bank B at simple interest for 10 years at the rate of 4% per annum. Find the total money she had, if she received same interest from both Bank.

  1. Rs. 560

  2. Rs. 1000

  3. Rs. 1500

  4. Rs. 1680

  5. Rs. 2000
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Interest from A = 1120 * 4 * 0.05 = 224. Let P be the amount in B. Interest from B = P * 10 * 0.04 = 0.4P. Since interests are equal, 0.4P = 224 => P = 560. Total money = 1120 + 560 = 1680.

Multiple choice

What will be the compound interest on the amount of Rs. 1,75,500 at a certain rate, if the simple interest on the same amount for 3 years is Rs. 31,590?

  1. Rs. 33,200

  2. Rs. 33,220

  3. Rs. 33,523

  4. Rs. 34,424

  5. Rs. 34,625
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Simple interest for 3 years is 31,590, so annual SI is 10,530. The rate is (10,530 / 1,75,500) * 100 = 6%. Compound interest for 3 years at 6% is 1,75,500 * ((1.06)^3 - 1) = 1,75,500 * 0.191016 = 33,523.308.