Quant quiz-Compound Interest

Quant quiz-Compound Interest

1.A man saves Rs 200 at the end of each year and lends the money at 5% compound interest. 

How much will it become at the end of 3 years.

A.Rs 662

B.Rs 662.01

C.Rs 662.02

D.Rs 662.03

E.none of these

2.Find the compound interest on Rs.16,000 at 20% per annum for 9 months, compounded quarterly

A.Rs 2520

B.Rs 2521

C.Rs 2522

D.Rs 2523

E.none of these

3.At what rate of compound interest per annum will a sum of Rs. 1200 become Rs. 1348.32 in 2 years

A.3%

B.4%

C.5%

D.6%

E.none of these

4.The least number of complete years in which a sum of money put out at 20% compound interest will be more than doubled is

A.4 years

B.5 years

C.6 years

D.7 years

E.none of these

5.Simple interest on a certain sum of money for 3 years at 8% per annum is half the compound interest on-

Rs. 4000 for 2 years at 10% per annum. The sum placed on simple interest is

A.Rs 1650

B.Rs 1750

C.Rs 1850

D.Rs 1950

E.none of these

6.What will be the difference between simple and compound interest @ 10% per annum on the sum of Rs 1000 after 4 years

A.Rs 62.10

B.Rs 63.10

C.Rs 64.10

D.Rs 65.10

E.none of these

7.The difference between simple and compound interests compounded annually on a certain sum of money for 2 years at 4% per annum is Rs 1. Find the sum

A.Rs 600

B.Rs 625

C.Rs 650

D.Rs 675

E.none of these

8.On a sum of money, simple interest for 2 years is Rs 660 and compound interest is Rs 696.30,

the rate of interest being the same in both cases.

A.8%

B.9%

C.10%

D.11%

E.none of these

9.If the simple interest on a sum of money for 2 years at 5% per annum is Rs. 50, 

what is the compound interest on the same at the same rate and for the same time?

A.Rs. 51.25 

B.Rs. 52

C.Rs. 54.25 

D.Rs. 60

E.none of these

10.The difference between compound interest and simple interest on an amount of Rs. 15,000 for -

2 years is Rs. 96. What is the rate of interest per annum?

A.8 

B.10

C.12 

D.Cannot be determined

E.None of these

Answers:

1. (c) 
Amount = Rs. [200 X (1+ 5/100)^3 + 200(1 +( 5/100))^2  + 200(1 + 5/100)                               
 = Rs. [200 X (21/20) X (21/20) X (21/20)  +200 X (21/20) X (21/20) + 200 X 21/20 ].
 = Rs. [200 X (21/20)[(21/20) X (21/20)  + (21/20) +1]
 = Rs. 662.02

2.C
Principal= Rs.16,000;
Time=9 months = 3 quarters;
Rate = 20%, it will be 20/4 = 5%
So lets solve this question now
Amount=16000(1+5/100)^3=18522
C.I=18522-16000=2522

3.D
Let Rate will be R
1200(1+R/100)^2=134832/100
(1+R/100)^2=134832/120000
(1+R/100)^2=11236/10000
(1+R/100)=106/100
R=6%

4.A
As per question we need something like following
P(1+R/100)^^n>2P
(1+20/100)^n>2
(6/5)^n>2
6/5�6/5�6/5�6/5>2
So answer is 4 years

5.B
C.I.=(4000�(1+10/100)^2-4000)
=4000*11/10*11/10-4000=840
So S.I. = 840/2=420
So Sum = (S.I.*100)/(R*T)
=(420*100)/(3*8)
=Rs1750

6.C
S.I.=(1000*10*4)/100=400
C.I.=[1000(1+10/100)^4-1000]=464.10
So difference between simple interest and compound interest will be
464.10 - 400 = 64.10

7.B

8.D
Difference in CI and SI for 2 years=Rs(696.30-660)=Rs 36.30
SI for one year = Rs 330.
therefore SI on Rs 330 for 1 year = Rs 36.30
therefore,Rate= (100*36.30/330*1)% = 11%

9.A

10.A
C.I.-S.I.=P(R/100)*(R/100)
96=15000(R/100)(R/100)
R*R=960/15=64
R=8