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

Find the interest and the amount, respectively on : Rs.$5,000$ at $8\%$ per year from $23^{rd}$ December $2003$ to $29^{th}$ July $2004$.
  1. Rs. $240$ and Rs. $5,640$
  2. Rs. $170$ and Rs. $4,970$
  3. Rs. $170$ and Rs. $5,270$
  4. Rs. $240$ and Rs. $5,240$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Time from Dec 23, 2003 to July 29, 2004: Dec(8) + Jan(31) + Feb(29) + Mar(31) + Apr(30) + May(31) + Jun(30) + Jul(29) = 219 days. Interest = (5000 * 8 * 219) / (100 * 366) = 239.34, approx 240. Amount = 5000 + 240 = 5240.

Multiple choice

What sum of money borrowed on $14^{th}$ june will amount to Rs $10,210.20$ on $7^{th}$ November of the same year at $5$ per cent per annum simple interest.
  1. Rs.$11,110$
  2. Rs.$9,015$
  3. Rs.$10,010$
  4. Rs.$10,520$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Time from June 14 to Nov 7: June(16) + July(31) + Aug(31) + Sept(30) + Oct(31) + Nov(7) = 146 days. 146 days = 146/365 = 0.4 years. Amount = P(1 + RT/100). 10210.20 = P(1 + (5*0.4)/100) = P(1 + 0.02) = 1.02P. P = 10210.20 / 1.02 = 10010.

Multiple choice

Sania lent some money to Manali at $5$% p.a. simple interest. Manali lent the whole amount to Niki on the same day at $ 10$% p.a. In this transaction, after a year Manali earned a profit of Rs $450$. Find the sum of money lent by Sania to M anali.
  1. Rs. $10000$
  2. Rs. $12000$
  3. Rs. $9000$
  4. Rs. $8000$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let the sum be P. Interest earned by Manali = 0.10P. Interest paid by Manali = 0.05P. Profit = 0.10P - 0.05P = 0.05P = 450. P = 450 / 0.05 = 9000.

Multiple choice

In 4 years, Rs 6500 amounts to Rs 8840 at a certain rate of interest. In what time will Rs 1600 amounts to Rs 1816 at the same rate?
  1. $3 years$
  2. $1.5 years$
  3. $2 years$
  4. $2.5 years$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Simple interest for 4 years = 8840 - 6500 = 2340. SI = P * r * t / 100. 2340 = 6500 * r * 4 / 100. 2340 = 260 * r. r = 2340 / 260 = 9%. Now, for 1600 to 1816: SI = 216. 216 = 1600 * 0.09 * t. 216 = 144 * t. t = 216 / 144 = 1.5 years.

Multiple choice

Arun borrowed a sum of money at the rate of $6\%$ per annum S.I. for the first two years, $9\%$ per annum for the next three years and $14\%$ per annum for the period beyond five years. If he pays a total of Rs. $11,400$ as interest only at the end of $9$ years, how much money did he borrow?
  1. $8,000$
  2. $15,200$
  3. $12,000$
  4. $60,800$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let P be the principal. Interest = P * (0.06*2 + 0.09*3 + 0.14*4) = 11400. P * (0.12 + 0.27 + 0.56) = 11400. P * 0.95 = 11400. P = 11400 / 0.95 = 12000.