Question

The sum of the length, breadth and height of a uniform cross sectional cuboid is $12cm$, and the height of its diagonal is $14cm$. Find the area of its total surface.

• A. $196c{m}^2$
• B. $166c{m}^2$
• C. $186c{m}^2$
• D. $176c{m}^2$

Answer 1

The correct option is A $196c{m}^2$

The sum of length, breadth and height $=a+b+c=12$
Diagonal $=\sqrt{a^2+b^2+c^2}=14$
Squaring on both sides, we get
$a^2+b^2+c^2={14}^2=196$
Surface area $=196c{m}^2$