Question

A certain sum amounts to Rs. 67600 in 2 years at $4 \%$ p.a. compound interest. Find the sum.

Answer 1

Let the sum be Rs. P, then

$\begin{array}{c}\text { Amount, } P\left(1+\frac{R}{100}\right)^{t}=67600 \\\Rightarrow P\left(1+\frac{4}{100}\right)^{2}=67600 \\\Rightarrow P\left(\frac{26}{25}\right)^{2}=67600 \\\Rightarrow P \times \frac{676}{625}=67600 \\\therefore P=\frac{67600 \times 625}{676} \\=62500 \text {; Ans. }\end{array}$