The cost of cultivating a square field at the rate of Rs. 685 per hector is Rs. 6165. The cost of putting a fence around it at the rate of Rs. 48.75 per metre would be :

Answer: Option C

$$\begin{array}{rl}& \text{Area}=\frac{\text{Total cost}}{\text{Rate}}\\ & =\left(\frac{6165}{685}\right)\text{hectares}\\ & =\left(9\times 10000\right)m^2\end{array}$$
∴ Side of the square :
$$\begin{array}{rl}& =\sqrt{90000}m\\ & =300m\end{array}$$
Perimeter of the field = (300 × 4) m = 1200 m
Cost of fencing = Rs. (1200 × 48.75) = Rs. 58500