Find the volume of wood used to make a closed box of outer dimensions 60 cm x 45 cm x 32 cm, the thickness of wood being 2.5 cm all around.
Given that,
External length = 60 cm
External width = 45 cm
External height = 32 cm
We know that,
Volume of cuboid = Length × Breadth × Height
Therefore,
External volume of the box = 60 × 45 × 32
= 86400 cm3
It is also given that,
Thickness of the wood = 2.5 cm
Therefore,
Internal length = 60 – (2.5 × 2) = 55 cm
Internal width = 45 – (2.5 × 2) = 40 cm
Internal height = 32 – (2.5 × 2) = 27 cm
As we know that,
Volume of cuboid = Length × Breadth × Height
Thereore,
Internal volume of the box = 55 × 40 × 27
= 59400 cm3
Hence,
Volume of wood = External volume – Internal volume
= 86400 – 59400
= 27000 cm3