Question

A room $5$ m long, $4.5$ m wide and $3.6$ m high has one door $1.5$ m by $2.4$ m and two windows, each $1$ m by $0.75$ m. If the area of its walls, excluding doors and windows is $x$, then $10x$ is

Answer 1

Two walls will have the dimensions $5$ m and $3.6$ m.
Other two walls will have the dimensions, $4.5$ m and $3.6$ m.
Each wall is in the shape of a rectangle.
Hence, area of the four walls of the room $=2(5\times 3.6)+2(4.5\times 3.6)=36+32.4=68.4m^2$
Subtracting the area of door and windows from the walls, we get $68.4-1.5\times 2.4-2(1\times 0.75)=68.4-3.6-1.5=63.3m^2$