Question:
Ishita invested a sum of Rs 12000 at 5% per annum compound interest. She received an amount of Rs 13230 after n years. Find the value of n.
Solution:
$\mathrm{A}=\mathrm{P}\left(1+\frac{\mathrm{R}}{100}\right)^{\mathrm{n}}$
$13,230=12,000\left(1+\frac{5}{100}\right)^{\mathrm{n}}$
$(1.05)^{\mathrm{n}}=\frac{13,230}{12,000}$
$(1.05)^{\mathrm{n}}=1.1025$
$(1.05)^{\mathrm{n}}=(1.05)^{2}$
On comparing both the sides, we get:
n = 2
Thus, the value of $\mathrm{n}$ is two years.