logo

CuriousTab

CuriousTab

Discussion


Home Aptitude Compound Interest See What Others Are Saying!
  • Question
  • The compound interest on a sum of ? 4000 becomes ? 630.50 in 9 months. Find the rate of interest, if interest is compounded quarterly.


  • Options
  • A. 20%
  • B. 23%
  • C. 19%
  • D. 21%

  • Correct Answer
  • 20% 

    Explanation

    Given, P =? 4000,
    n = 9 months = 3/4 yr and
    CI = ? 630.50
    Amount = P + CI = 4000 + 630.50 = ? 4630.50

    According to the formula,
    ? Amount = P[(1+R/(100 x 4)]4n
    ? 4630.50 = 4000(1+R/400)4 x 3/4
    ? 4630.50 = 4000[(400 + R)/400]3
    ? 4630.50/4000 = [(400 + R)/400]3
    ? 9261/8000 = [(400 + R)/400]3
    ? (21/20)3 = [(400 + R)/400]3
    ? [(400 + R)/400]/400 = 21/20
    ? 400 + R = 21 x 20 = 420
    ? R = 420 - 400 = 20%


  • More questions

    • 1. The milk and water in two vessels are in the ratio of 3 : 1 and 7 : 11 respectively. In what ratio should the liquid in both the vessels be mixed to obtaina new mixture containing half milk and half water?

    • Options
    • A. 5 : 7
    • B. 4 : 9
    • C. 1 : 1
    • D. 4 : 7
    • Discuss
    • 2. In a mixture of 35 litres, the ratio of milk and water is 4:1. If 7 litres of water is added to the mixture, the ratio of milk and water of the new mixture will be

    • Options
    • A. 2:1
    • B. 1:2
    • C. 4:5
    • D. 5:4
    • Discuss
    • 3. 
      If the three- fourth of number is subtracted from the number, the value so obtained is 163. What is that number?

    • Options
    • A. 625
    • B. 562
    • C. 632
    • D. 652
    • Discuss
    • 4. 8 litres are drawn from a flask containing milk and then filledwith water. The operation is performed 3 more times. Theratio of the quantity of milk left and total solution is 81/625.How much milk the flask initially holds?

    • Options
    • A. 10 ltr
    • B. 20 ltr
    • C. 30 ltr
    • D. 40 ltr
    • Discuss
    • 5. The square root of 64009 is:

    • Options
    • A. 253
    • B. 347
    • C. 363
    • D. 803
    • Discuss
    • 6. 4, -8, 16, -32, 64, (....)

    • Options
    • A. 128
    • B. -128
    • C. 192
    • D. -192
    • Discuss
    • 7. 
      6.39 x 128.948 + 5.215 ÷ 12.189 + 25.056 =?

    • Options
    • A. 800
    • B. 900
    • C. 850
    • D. 950
    • Discuss
    • 8. 
      A 240 m long train crosses a platform of equal length in 27 s. What is the speed of the train in km/h?

    • Options
    • A. 48
    • B. 60
    • C. 56
    • D. 64
    • Discuss
    • 9. 
      If 1 / 3.718 = .2689, then the value of 1 / .0003718 is?

    • Options
    • A. 2689
    • B. 2.689
    • C. 26890
    • D. .2689
    • Discuss
    • 10. 
      A can do a piece of work in 24 days. If B is 60% more efficient than A, then the number of days required by B to do the same piece of work is?

    • Options
    • A. 10
    • B. 15
    • C. 12
    • D. 9.6
    • Discuss


    Comments

    There are no comments.

Enter a new Comment