ANSWER:
Rate per annum at which CI will amount from RS 2000 to RS 2315.35 in 3 years is 5%
SOLUTION:
Given,
P = RS 2000
C.I = RS 2315.35
T = 3 years
We need to find the rate per annum. i.e. R = ?
We know that,
When interest is compound Annually:
[tex]Amount $=\mathrm{P}\left(1+\frac{\mathrm{R}}{100}\right)^{n}$[/tex]
Where p = principal amount
r = rate of interest
n = number of years
[tex]$2315.35=2000 \times\left(1+\frac{R}{100}\right)^{3}$[/tex]
[tex]$\left(1+\frac{R}{100}\right)^{3}=\frac{2315.35}{2000}$[/tex]
[tex]$\left(1+\frac{R}{100}\right)^{3}=1.157$[/tex]
[tex]$1+\frac{R}{100}=\sqrt[3]{1.157}$[/tex]
[tex]$1+\frac{R}{100}=1.0500$[/tex]
[tex]$\frac{R}{100}=1.05-1$[/tex]
[tex]$\frac{R}{100}=0.05$[/tex]
R = 5%
Hence, rate per annum is 5 percent.
