Simple Interest Set – 2

1. A person makes a fixed deposit of Rs. 20000 in Bank of India for 3 years. If the rate of interest be 13% SI per annum charged half yearly. What amount will he get after 42 months?
   A. 29100
   B. 28100
   C. 27100
   D. 26100
   
   A. 29100
   Explanation:
   R=13%, T= 42 months
   For half year
   R=13/2, T= (42/12)*2= 7 half-years
   SI= (20000*7*6.5/100) = 9100
   A= P+SI = 20000+9100=29100
   
   
2. Rakesh invests Rs 12000 as fixed deposit at a bank at the rate of 10% per annum SI. But due to some pressing needs he has to withdraw the entire money after 3 years,  for which the bank allowed him a lower rate of interest. If he gets Rs 3320 less than what he would have got at the end of 5 years, the rate of interest allowed by the bank is
   A. 68/9%
   B. 64/9%
   C. 67/9%
   D. 61/9%
   
   C. 67/9%
   Explanation:
   P=12000, T1=10 years, T2=3 years, R1=10%, R2=?
   [(12000*10*5)/100 – (12000*R2*3)/100] = 3320
   => 50-3R2 = 83/3
   => R2 = 67/9%
   
   
3. Ankita borrowed some money from at the rate of 6% per annum for the first 3 year, @ the rate of 9% per annum for the next 5 year and @ the rate of 13% per annum for the period beyond 8 year. If she pays a total interest of Rs.8160 at the end of 11 year. How much money did she borrow?
   A. 10000
   B. 8000
   C. 6000
   D. 4000
   
   B. 8000
   Explanation:
   T1=3, T2=5, T3= Period beyond 8 year, so T3= total years-8 = 11-8 =3
   Let the amount borrowed = P
   [(P*6*3)/100 (P*9*5)/100 (P*13*3)/100] = 8160
   [102P/100] = 8160
   P=8000
   
   
4. A father left a will of Rs.35 lakhs between his two sons aged 8.5 and 16 such that they may get equal amounts when each of them reach the age of 21 years. The original amount of Rs.35 lakhs has been instructed to be invested at 10% p.a. SI. How much did the elder son get at the time of the will?
   A. 20 lakh
   B. 28 lakh
   C. 21 lakh
   D. 23 lakh
   
   C. 21 lakh
   Explanation:
   Let x be the amount of elder son at the time of will & Younger son’s amount at the time of will (350000 -x)
   For elder son, T= 21-16=5
   For younger son, T=21-8.5= 12.5
   Amount Should be equal so,
   x + [(x*10*5)/100] = (3500000-x) + [((3500000-x)*10*12.5)/100]
   => 5x/3 = 3500000
   x=2100000
   
   
5. A portion of Rs.6600 is invested at a 5% per annum, while the remainder is invested at a 3% per annum. If the annual income from the portion earning a 5% per annum is twice that of the other portion, what is the total income from the two investments after one year?
   A. Rs.270
   B. Rs.370
   C. Rs.250
   D. Rs.280
   
   A. Rs.270
   Explanation:
   5x + 3y = z (Total Income)
   x + y = 6600 -(1)
   5x= 2(3y)
   5x – 6y = 0 -(2)
   By solving (1) and (2) we get, x = 3600 so y = 3000
   (3600*5*1)/100 + (3000*3*1)/100 = 180 + 90 = 270
   
   
6. Simple Interest for the sum of Rs.1230 for two year is Rs.10 more than the SI for Rs.1130 for the same duration. Find the Rate of Interest?
   A. 5%
   B. 8%
   C. 4%
   D. 2%
   
   A. 5%
   Explanation:
   (1230*2*R)/100 – (1130*2*R)/100 = 10
   R=5%
   
   
7. Arvind borrowed Rs.800 at 6% per annum and Deepak borrowed Rs.600 @ 10% per annum. After how much time, will they both have equal debts?
   A. 50/3 yr
   B. 83/3 yr
   C. 44/3 yr
   D. 20/3 yr
   
   A. 50/3 yr
   Explanation:
   800+(800*6*T)/100 = 600+(600*10*T)/100
   T=50/3 yr
   
   
8. The Principal on which a simple interest of Rs.55 will be obtained after 9 months at the rate of 11/3% per annum is ___________
   A. 2500
   B. 1500
   C. 1000
   D. 2000
   
   D. 2000
   Explanation:
   SI =PRT/100
   P = 100*55/(11/3)*(9/12)
   P = 100*55*4/11
   P = 2000
   
   
9. The rate of Simple Interest in UBI & BOI are in the ratio of 5:4. Mr.Naveen wants to deposit his total savings in two banks in such a way that he receive equal half-yearly interest from both banks.He should deposit in both banks UBI & BOI in the ratio of
   A. 2:5
   B. 1:5
   C. 4:5
   D. 3:5
   
   C. 4:5
   Explanation:
   R1 =5x R2=4x T1=T2=1/2 yr
   [P1*5x*(1/2)]/100 = [P2*4x*(1/2)]/100
   P1:P2 = 4:5
   
   
10. A sum becomes 3 times in 5 year at a certain rate of interest. Find the time in which the same amount will be eight times at the same rate of interest?
    A. 45/2 yr
    B. 35/2 yr
    C. 25/2 yr
    D. 15/2 yr
    
    B. 35/2 yr
    Explanation:
    T=5, SI = 3P-P =2P
    2P = P*R*5/100
    R = 40%
    For another time
    SI = 8P-P =7P
    7P = P*40*T/100
    T=35/2