Question

Find the volume of wood used to make a closed rectangular box of outer dimensions 65cm×45cm×35cm.The thickness of wood being 2•5cm all around. Also find the capacity of the box​

Answer 1

Solution :

External length = 60 cm,

external breadth = 45 cm

external height = 35 cm.

External volume

= (65 × 45 × 35) cm

= 102375 cm³

Internal length

= (65-(2.5 × 2))

= (65 - 5) cm

= 60 cm.

Internal breadth

= (45-(2.5 × 2))

= (45 - 5) cm

= 40 cm

Internal height

= (35 -(2.5 × 2))

= ( 35 - 5) cm

= 30 cm

internal volume

= (60 × 40 × 30) cm³

= 72000 cm³

capacity of the of wood box = internal volume

= 72000 cm³,

volume used to make the

= (external volume) - (internal box volume)

= (102375 - 72000) cm³

= 30375 cm³