Question

Find the curved surface area of frustum cone radii 3 and 9 cm and a slant height 12 cm.

• A. 144 $\pi c{m}^2$
• B. 134 $\pi c{m}^3$
• C. 124 $\pi c{m}^3$
• D. 114 $\pi c{m}^3$

Answer 1

The correct option is A 144 $\pi c{m}^2$

Curved surface area = $\pi$(R + r)s

= $\pi (9+3)\times 12$

= $\pi \left(12\right)\times 12$

= 144 $\pi c{m}^2$