Question

The difference of compound interest and simple interest  for 3 years at 9% per annum on certain sums is Rs.60. Then the present value of a sum is ​

Answer 1

Step-by-step explanation:

Let principle amount =x

Simple interest =  

100

P×R×T

​  

 

P=Principle=x

R=Rate=10% Per annum

T=Time =3 years

⇒S.I=  

100

x×10×3

​  

=  

10

3x

​  

 

Compound interest=Amount − Principle

Amount =P(1+  

100

R

​  

)  

T

 

=x(1=  

100

10

​  

)  

3

 

=x(  

10

11

​  

)  

3

 

⇒C.I=  

1000

1331x

​  

−x

=  

1000

1331x−1000x

​  

 

=  

1000

331x

​  

 

Difference of C.I and S.I=93

⇒  

1000

331x

​  

−  

10

3x

​  

=93

⇒  

1000

31x

​  

=93

⇒x=  

31

93×1000

​  

=3000Rs.

⇒ Sum =3000Rs.