Question

Find the principal if the interest compounded annually at the rate of 10% for two years is Rs 210. (in Rs)

Answer 1

Given:

$Rate\left(R\right)=10$

$Time\left(n\right)=2years$

$Compoundintrest(C.I)=Rs.210$

To find:

Principle(P)

We know that:

$C.I=P[{(1+\frac{R}{100})}^n-1]$

Solution:

$\Rightarrow C.I=P[{(1+\frac{R}{100})}^n-1]$

$\Rightarrow 210=P[{(1+\frac{10}{100})}^2-1]$

$\Rightarrow 210=P[{\left(\frac{110}{100}\right)}^2-1]$

$\Rightarrow 210=P[{\left(1.1\right)}^2-1]$

$\Rightarrow 210=P[1.21-1]$

$\Rightarrow 210=P\left[0.21\right]$

$\Rightarrow P=\frac{210}{0.21}$

$\Rightarrow P=1000$

$\therefore \text{the required answer is}Rs.1000$