Question

The compound interest on Rs. $30,000$ at $7\%$ per annum Rs. $4347$. The period ( in years) is

• A. $2$
• B. $2\frac{1}{2}$
• C. $3$
• D. $4$

Answer 1

Answer: (A)

$2$

$P=$ Rs. $30000,r=7\%$ p.a. $C.I.$ $=$ Rs. $4347,n=?$
$\Rightarrow$ Amount $=$ Rs. $30000+$ Rs. $4347=$ Rs. $34347$
$\therefore 34347=30000{(1+\frac{7}{100})}^n$

$\Rightarrow {\left(\frac{107}{100}\right)}^n=\frac{34347}{30000}=\frac{11449}{10000}$
$\Rightarrow {\left(\frac{107}{100}\right)}^n={\left(\frac{107}{100}\right)}^2$

$\Rightarrow n=2$