Question

A cuboidal room is $1\frac{1}{2}$ as long as it is broad. The cost of carpeting the walls with coloured paper at the rate of $Rs.3$ per sq. mts is $Rs.360$. Find the dimensions of the room.

Answer 1

let suppose breadth be ' B ' then length will be (3/2)B or 1.5B

the area of 4 walls will be 4 x L x B

then area = $4\ast B\ast 1.5B$

= $6B^2$

the total cost is 360 at the rate of Rs 3 per sq. mt

Therefore, the cost= $360/3$

=$180$ (area)

area of walls = 180

$6B^2=180$

$B^2=30$

$B=\sqrt{3}0$

$B=5.477m$

$L=1.5xB$

$L=8.21m$