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

A sum was invested on simple interest at a certain rate for 2 years. If the interest rate is increased by 4%, then the interest increases by Rs. 160. What is the sum (in Rs.) invested?

  1. 2,000

  2. 3,000

  3. 3,500

  4. 4,000
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Simple interest formula is I = P*R*T/100. The increase in interest is (P * (R+4) * 2 / 100) - (P * R * 2 / 100) = 160. This simplifies to P * 4 * 2 / 100 = 160, so P * 0.08 = 160. P = 160 / 0.08 = 2000.

Multiple choice

A man deposited a certain sum in a bank. He gets 5% per annum interest for the first year, 4% for the next 2 years and 3% for the next 3 years. If he gets Rs. 1760 as simple interest for 6 years, then how much money did he deposit in the bank?

  1. Rs. 8000

  2. Rs. 6000

  3. Rs. 4000

  4. Rs. 5000

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

Let P be the principal. Interest = P * (rate * time) / 100. Interest = P * [(5*1) + (4*2) + (3*3)] / 100 = P * (5 + 8 + 9) / 100 = 22P / 100. 1760 = 0.22P. P = 1760 / 0.22 = 8000.