Question

The perimeter of a floor of a room is 30 m and its height is 3 m. Find the area of four walls of the room.

Answer 1

$$\begin{gathered} \mathrm{Perimeter}\mathrm{of}\mathrm{the}\mathrm{floor}\mathrm{of}\mathrm{the}\mathrm{room}=30\mathrm{m} \\ \mathrm{Height}\mathrm{of}\mathrm{the}\mathrm{oom}=3\mathrm{m} \\ \mathrm{Perimeter}\mathrm{of}\mathrm{a}\mathrm{rectangle}=2\times (\mathrm{length}+\mathrm{breadth})=30\mathrm{m} \\ \mathrm{So},\mathrm{area}\mathrm{of}\mathrm{the}\mathrm{four}\mathrm{walls}=2\times (\mathrm{length}\times \mathrm{height}+\mathrm{breadth}\times \mathrm{height}) \\ =2\times (\mathrm{length}+\mathrm{breadth})\times \mathrm{height} \\ =30\times 3=90{\mathrm{m}}^2 \end{gathered}$$