Find the volume of wood used to make a closed box of outer dimensions 60 cm×45 cm×32 cm , the thickness of wood being 2.5 cm all around.
Outer length of wooden box (L)=60 cm
Width (B)=45 cm.
and height (H)=32 cm.
∴ Thickness of wood used =2.5 cm.
∴ Inner length (l) =60−2×2.5=60−5=55cm
Width(b) =45−2×2.5=45−5=40cm
and height (h) =32−2×2.5=32−5=27cm
Now outer volume =L×B×H=60×45×32cm3
Inner volume =l×b×h=55×40×27
∴ Volume of wood =60×45×32−55×40×27
=86400−59400=27000cm3