Question

The circumference of lower and upper bases of the frustum cone is 11 and 23 m. The slant height is 12 m. What is the curved surface area ?

• A. 204 $m^2$
• B. 300 $m^2$
• C. 200 $m^2$
• D. 100 $m^2$

Answer 1

The correct option is A 204 $m^2$

Curved surface area of the frustum cone

= $\frac{1}{2}(2\pi R+2\pi r)l$

= $\frac{1}{2}(11+23)\times 12$

= $34\times 6$

= 204 $m^2$