Question

The floor of a room which measures 3m by 4m is to be covered with tiles. the tiles are 20cm square. How many tiles are needed?

Answer 1

$$\begin{gathered} \mathrm{Length}\mathrm{of}\mathrm{the}\mathrm{floor}\mathrm{of}\mathrm{the}\mathrm{room}=4\mathrm{m}=400\mathrm{cm}\left[\mathrm{as},1\mathrm{m}=100\mathrm{cm}\right] \\ \mathrm{breadth}\mathrm{of}\mathrm{floor}\mathrm{of}\mathrm{the}\mathrm{room}=3\mathrm{m}=300\mathrm{cm} \\ \mathrm{area}\mathrm{of}\mathrm{the}\mathrm{floor}\mathrm{of}\mathrm{the}\mathrm{room}=\mathrm{length}\times \mathrm{breadth}=400\times 300=120000{\mathrm{cm}}^2 \\ \mathrm{now},\mathrm{area}\mathrm{of}\mathrm{each}\mathrm{tile}=20{\mathrm{cm}}^2 \\ \mathrm{no}.\mathrm{of}\mathrm{tiles}\mathrm{required}=\frac{\mathrm{area}\mathrm{of}\mathrm{the}\mathrm{floor}\mathrm{of}\mathrm{the}\mathrm{room}}{\mathrm{area}\mathrm{of}\mathrm{each}\mathrm{tile}}=\frac{120000}{20}=6000 \end{gathered}$$