Question

Teju invests Rs. 12,000 at 5% interest compounded annually. If he receives an amount Rs. 13,230 at the end, find the period.

Answer 1

Given : $P=12000,R=5,A=13230$

To find $n$

We know that,

$A=P{(1+\frac{R}{100})}^n$

$⟹13230=12000{(1+\frac{5}{100})}^n$

$⟹\frac{13230}{12000}={\left(\frac{21}{20}\right)}^n$

$⟹\frac{441}{400}={\left(\frac{21}{20}\right)}^n$

$⟹{\left(\frac{21}{20}\right)}^2={\left(\frac{21}{20}\right)}^n$

$⟹n=2$

Hence, the period of time is $2$ years.