Question

The area of the four walls in a room is $120{\text{m}}^2$. The length is twice the breadth. If the height of the room is $4$ m, find the area of the floor.

Answer 1

$l=2b$

$h=4m$

Area fof four walls $A=2(l+b)h$

$⟹120=2\times 4(2b+b)$

$⟹b=5m$

Area of floor$=lb=2b.b=2b^2=2\times 5^2$

$=50m^2$