Question

The floor of a building consists of 800 tiles,which are rhombus shaped and each of its diagonals are 30 cm & 45 cm in length.Find the total cost of polishing the floor. If the cost per metre square is Rs. 8/-

Answer 1

$$\begin{gathered} \mathrm{Length}\mathrm{of}\mathrm{first}\mathrm{diagonal}\mathrm{of}\mathrm{a}\mathrm{tile}={\mathrm{d}}_1=30\mathrm{cm} \\ \mathrm{length}\mathrm{of}\mathrm{the}\mathrm{second}\mathrm{diagonal}\mathrm{of}\mathrm{a}\mathrm{tile}={\mathrm{d}}_2=45\mathrm{cm} \\ \mathrm{Area}\mathrm{of}1\mathrm{tile}=\frac{1}{2}\times {\mathrm{d}}_1\times {\mathrm{d}}_2=\frac{1}{2}\times 30\times 45=15\times 45=675{\mathrm{cm}}^2=0.0675{\mathrm{m}}^2 \\ \mathrm{Area}\mathrm{of}800\mathrm{tiles}=800\times 0.0675=54{\mathrm{m}}^2 \\ \mathrm{Cost}\mathrm{of}\mathrm{polishing}1{\mathrm{m}}^2\mathrm{area}=\mathrm{Rs}8 \\ \mathrm{Cost}\mathrm{of}\mathrm{polishing}54{\mathrm{m}}^2\mathrm{area}=\mathrm{Rs}\left(8\times 54\right)=\mathrm{Rs}432 \end{gathered}$$