Question

Find the volume of wood used to make a closed box of outer dimensions $60cm\times 45cm\times 32cm$ , the thickness of wood being 2.5 cm all around.

Answer 1

Outer length of wooden box (L)=60 cm

Width (B)=45 cm.

and height (H)=32 cm.

$\therefore$ Thickness of wood used =2.5 cm.

$\therefore$ Inner length (l) $=60-2\times 2.5=60-5=55cm$

Width(b) $=45-2\times 2.5=45-5=40cm$

and height (h) $=32-2\times 2.5=32-5=27cm$

Now outer volume $=L\times B\times H=60\times 45\times 32c{m}^3$

Inner volume $=l\times b\times h=55\times 40\times 27$

$\therefore$ Volume of wood $=60\times 45\times 32-55\times 40\times 27$

$=86400-59400=27000c{m}^3$