Question

If a rectangular prism has length $l=12$ units, width $w=8$ units and height $h=5$ units. Match the following.

• A. $196$ sq. units
• B. $200$ sq. units
• C. $480$ sq. units

Answer 1

Given length, width and height of the rectangular prism as
$l=12;w=8;h=5$ units.


Here, the total surface area of the rectangular prism
$=2\times (l\times w+w\times h+h\times l)$
$=2\times (12\times 8+8\times 5+5\times 12)$
$=2\times (96+40+60)$
$=392$ sq. units.

For lateral surface area we exclude the areas of the top and the bottom surface.
$\therefore$ Lateral surafce area $=2\times (l\times w+w\times h)$
$=2\times (12\times 5+8\times 5)$
$=2\times (60+40)$
$=200$ sq. units

For the volume we have:
$=l\times w\times h$
$=12\times 8\times 5$
$=480$ cubic units.