Question

The floor of a building consists of $3000$ tiles which are rhombus shaped and each of its diagonals are $45cm$ and $30cm$ in length. Find the total cost of polishing the floor if the cost per $m^2$ is $Rs.4$.

Answer 1

Given diagonals of rhombus are

$d_1=45cm$

$d_2=30cm$

Number of tiles = $3000$

Rate per $m^2=4$

$\therefore$ Area of rhombus $=\frac{1}{2}\times d_1\times d_2$

$=\frac{1}{2}\times 45\times 30$

$=675c{m}^2$

Area of 1 tile $=675c{m}^2=\frac{675}{10000}{m}^2.......[1c{m}^2.\frac{1}{1000}{m}^2]$

Area of $3000$ tiles $=[3000\times \frac{675}{10000}]$

Cost of polishing the floor $=TotalArea\times Rate$

$=\frac{3000\times 675\times 4}{10000}$

$=\frac{3\times 675\times 4}{10}$

$=12\times 67.5$

$=Rs.810$

$\therefore$ Hence the total cost of polishing the floor = $Rs.810$