Question

the difference between compound interest and simple interest on Rs 42000 for 2 years is Rs 105 at the same rate of interest per annum. Find the CI earned in 2 years ​

Answer 1

Answer:

Step-by-step explanation:Solution

verified

P = Rs 42000 T=2 years

Let rate = r %

S.I=  

100

PRT

​

=  

100

42000×r×2

​

=840 Rs

For C.I

A=P(1+  

100

r

​

)  

n

 

=42000(1+  

100

r

​

)  

2

 

=42000(1+  

10000

r  

2

 

​

+  

50

r

​

)

=42000+  

10

42r  

2

 

​

+840r

C.I = A - P

=42000+  

10

42r  

2

 

​

+840r−42000

=  

10

42r  

2

 

​

+840r

Given C.I−S.I=105

=  

10

42r  

2

 

​

+840r−840r=105

=  

10

42r  

2

 

​

=105

=42r  

2

=1050

=r  

2

=25

r=5%

C.I at 2nd year = 42000(1+  

100

5

​

)  

2

−42000

=42000(1.1025−1)=4305 Rs