Question

The base of a prism is a rectangle of sides 5 cm and 12 cm and its height is 20 cm. It is split vertically along the diagonal of the base into two triangular prisms. What is the lateral surface area of each of these triangular prisms?

• A. $800c{m}^2$
• B. $400c{m}^2$
• C. $600c{m}^2$
• D. $200c{m}^2$

Answer 1

The correct option is C

$600c{m}^2$

Base of the prism has length and breadth 5 cm and 12 cm respectively.

Diagonal of base $=\sqrt{(12{)}^2+5^2}=\sqrt{169}=13cm$

Lateral Surface Area = $BasePerimeter\times height$

$=(12+5+13)20$

$=30\times 20$

$=600c{m}^2$

Lateral surface area of each of the triangular prisms$=600c{m}^2$