Quantitative Aptitude: Simple/Compound Interest Set 19

  1. The difference between simple interest and compound interest on a sum of rs.4400 for 2years is rs.44. What is the rate of interest per annum?
    10%
    15%
    12%
    18%
    20%
    Option A
    Solution: Let the rate of interest be r% per annum.
    ATQ,
    4400×r^2/(100×100)=44
    r= 10%

     

  2. If the sum of money gets tripled at a certain rate of simple interest in three years, in how many years it will become 9 times of it self with same rate of interest?
    15 years
    9 years
    27 years
    10 years
    12 years
    Option E
    Solution: Let the amount be P and rate of interest be R% per annum.
    ATQ,
    (3P-P)=P×R/100×3
    R=200/3
    Let us the assume that in t years amount will become 18 times itself .
    ATQ,
    (9P-P)=P×200/3×t/100
    t=12 years

     

  3. Difference between the simple interest received in 1.5 years at 24% per annum and that received in 3.5 years at 12% per annum on the same sum is Rs.1440, then find the sum ?
    22000
    30000
    15000
    24000
    26000
    Option D
    solution: 100x*3.5*12/100 – 100X*1.5*24/100=1440
    42x-36x=1440
    x=240
    Required sum = 100x
    =100*240=24000

     

  4. A lent of Rs.3000 to B for 2 years and Rs.1000 to C for 4 years on simple interest at the same rate of interest and received Rs.500 in all from both of them as interest. The rate of interest per annum is ,
    10%
    8%
    6%
    9%
    5%
    Option E
    solution: 3000*r/100*2+1000*r/100*4=500
    60r+40r=500
    r=5%

     

  5. The interest earned on a certain sum in 2years at 20% pa at CI is twice the interest earned on Rs.2200 for 2years at 10% SI. Find the value of sum.
    3000
    2000
    2250
    1280
    1600
    Option B
    Solutions: p(1+r/100)^2-p=2*2200*10*2/100=880
    p36/25-p=880
    p=2000

     

  6. Ram divided his total amount between his brother and sister in the ratio 5:3. His brother invested his share on CI for two years at the rate of 10% and received the interest rs.480 less than his sister ,who invested her share on SI for three years at the rate of 15%. find the share of individual Ram’s brother and sister respectively.
    8000,4800
    6400,5000
    4800,3500
    5000,3000
    none of these
    Option A
    Solution: Let total savings of Ram is rs.8x
    share of his brother =rs. 5x
    and share of sister =rs.3x
    CI received by his brother = 5p [(1+10/100)^2-1]=105p/100
    ATQ, 3p*15/100*3-105p/100=480
    135p/100-105p/100=480
    30p=48000
    p=rs.1600
    Ram’s brother share=1600*5=rs.8000
    Ram’s sister share=1600*3=rs.4800

     

  7. Rajat invested rs.P on CI of the rate of 10% for 2 years and suman invested rs.Q on SI at the rate of 20% for 3 years and ratio of interest got by Rajat in 2nd year and total interest got by Suman is 1:3. If Rahul invested rs (P+Q) on SI for 2 years on 12% p.a. and gets rs. 372 as interest. Find amount of Rajat and Suman invested individually.
    1000,550
    1600,800
    1200,900
    1500,600
    none of this
    Option
    Solution: 2nd year CI on 10% =10+10*10/100=11%
    total 3 year SI at 20%=20*3=60%
    According to questions , 11P/60Q=1/3
    P=1/3*60/11=20Q/11
    also given, (20Q/11+Q)*12/100*2=372
    31Q/11*24/100 = 372
    Q =372*1100/31*24
    Q=rs. 550
    P=20*550/11 =rs.1000

     

  8. Srikatnta invested a sum of rs.20,000 in a scheme offering simple interest at 30% p.a. after 2 years, he again invested total money he got from scheme in share market of 80 per share, after 3 month he sold all his share at rs. 100 per share. Find his total profit.
    8000
    10,000
    6000
    9000
    none of this
    Option A
    Solution: Amount = 20000+20,000*30*2/100=rs.32,000
    Units of share parched =32000/80=400
    selling price of share =400*100=40,000
    Profit = 40,000-32000=8000

     

  9. The simple interest accrued on a certain sum is rs. 5000 in 4 years at the rate of 10 p.a. What would be the compound interest accrued on the same sum at the same rate in years ?
    3100
    2625
    1200
    1400
    none of this
    Option B
    solution: Let the sum be rs.x
    x*10/100*4=5000
    x=12500
    CI for 2years @ 10%=10+10*10*10/100
    =21%
    21% of 12500 =2625

     

  10. A invested total of rs.80,000 in two schemes M and N for 2 years. In scheme M he invested at 18% p.a. at SI and in scheme N he invested at 20% p.a at CI compounded annually. If SI received is rs.4800 more than CI, then find amount invested by him in scheme N.
    50,000
    30,000
    40,000
    20,000
    none of these
    Option B
    solutions: Let amount invested in scheme N =x
    and in scheme M =80000-x
    rate of interest of scheme N=20+20+20*20/100=44%
    [(80000-x)18*2/100]-44x/100=4800
    2880000-36x/100-44x/100=4800
    80x=2400000
    x=30000