Question

A square tank has an area of 1600 m². There are four semicircular plots around it. Find the cost of turfing the plots at Rs 1.25 per m².

Answer 1

Area of the square = ${\mathrm{Side}}^2$
$$\begin{gathered} \Rightarrow 1600={\mathrm{Side}}^2 \\ \Rightarrow \mathrm{Side}=40\mathrm{m} \end{gathered}$$

Each piece of land is a semicircle, area = $\frac{1}{2}\times 3.14\times 20\times 20=\frac{22\times 10\times 20}{7}=628{\mathrm{m}}^2$

Total area = $4\times 628.57=2512{\mathrm{m}}^2$

Cost of turfing at Rs 1.25 per sq. m = $1.25\times 2512=\mathrm{Rs}3140$