Question

A room 4.9 m long and 3.5 m broad is covered with carpet, leaving an uncovered margin of 25 cm all around the room. If the breadth of the carpet is 80 cm, find its cost at Rs 40 per meter.

Answer 1

Width of the room left uncovered = 0.25 m
Now,
Length of the room to be carpeted = $4.9-\left(0.25+0.25\right)=4.9-0.5=4.4\mathrm{m}$
Breadth of the room be carpeted = $3.5-\left(0.25+0.25\right)=3.5-0.5=3\mathrm{m}$

Area to be carpeted = $4.4\times 3=13.2{\mathrm{m}}^2$

Breadth of the carpet = 80 cm = 0.8 m
We know:
Area of the room = Area of the carpet

$$\begin{gathered} \mathrm{Length}\mathrm{of}\mathrm{the}\mathrm{carpet}=\frac{\mathrm{Area}\mathrm{of}\mathrm{the}\mathrm{room}}{\mathrm{Breadth}\mathrm{of}\mathrm{the}\mathrm{carpet}} \\ =\frac{13.2}{0.8} \\ =16.5\mathrm{m} \end{gathered}$$

Cost of 1 m carpet = Rs 40
Cost of 16.5 m carpet = $40\times 16.5=\mathrm{Rs}660$