Question

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

• A. 1
• B. 2
• C. 3
• D. 3.5

Answer 1

The correct option is B

2

Let the period be n years.
Then, amount after n years = Rs.(30000 + 4347) = Rs. 34347

$\Rightarrow P(1+\frac{R}{100}{)}^n=34347$

$\Rightarrow 30000(1+\frac{7}{100}{)}^n=34347$

$\Rightarrow 30000(\frac{107}{100}{)}^n=34347$

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

$\Rightarrow n=2years$