A money lender finds that due to fall in the annual rate of interest from 8% to 73/4 %, his yearly income diminishes by Rs. 61.50. His capital is = ?

Answer: Option C

Let initial capital = 100 units

According to the question,
$$\begin{array}{rl}& \frac{1}{4}\text{unit = Rs}\text{. 61}\text{.50}\\ & \text{1 unit = Rs}\text{. 61}\text{.50}\times \text{4}\\ & \text{ = Rs}\text{. 246}\\ & \text{100 units = Rs}\text{. 24600}\end{array}$$
Hence,
Required capital = Rs. 24600

Alternate
Difference in percentage
\begin{aligned} & {\text{ = 8% }} - \frac{{31}}{4}\% \\ & \Leftrightarrow \frac{1}{4}\% = 61.50 \\ & \Leftrightarrow 100\% = 24600 \\\end{aligned}