Question:
The surface area of a cuboid is 758 cm2. Its length and breadth are 14 cm and 11 cm respectively. Find its height.
Solution:
Length of the cuboid = 14 cm
Breadth of the cuboid = 11 cm
Let the height of the cuboid be x cm.
Surface area of the cuboid = 758 cm2
Then $758=2(14 \times 11+14 \times x+11 \times x)$
$\Rightarrow 758=2(154+14 x+11 x)$
$\Rightarrow 758=2(154+25 x)$
$\Rightarrow 758=308+50 x$
$\Rightarrow 50 x=758-308=450$
$\Rightarrow x=\frac{450}{50}=9$
∴ The height of the cuboid is 9 cm.