Question

A closed box measures 66 cm, 36 cm and 21 cm from outside. If its walls are made of metal-sheet, 0.5 cm thick; find:

i) The capacity of the box;

ii) Volume of metal - sheet and

iii) Weight of the box, if $1c{m}^3$ of metal weights 3.6 gm.

Answer 1

External length of the closed box = 66 cm.
External breadth of the closed box = 36 cm.
External height of the closed box = 21 cm.
External volume of the closed box $=66\times 36\times 21$
$=49896c{m}^3$
Internal length of the box $=(66-2\times 0.5)$
= 66 - 1 = 65 cm
Internal breadth of the box $=(36-2\times 0.5)$
=36-1=35 cm
Internal height of the box $=(21-2\times 0.5)$
= 21 - 1 = 20 cm
Internal volume of the box $=65\times 35\times 20$
$=45500c{m}^3$
i) Capacity of the box $=45500c{m}^3$
ii) Volume of metal sheet of the box = External volume - Internal volume
= 49896 - 45500
$=4396c{m}^3$
iii) $1c{m}^3$ of metal weigh 3.6 grams
$\therefore$ Weight of the box $=4396\times 3.6$ gm
= 15825.6 gm.