Question

The curved surface area of frustum cone is $303.3$ $i{n}^2$. The diameter of a top cone is $0.5$ and the radius of the bottom cone is $0.2$ in. Find the slant height. (Use $\pi$ = 3.14).

• A. 281.49 in
• B. 282.49 in
• C. 214.64 in
• D. 285.49 in

Answer 1

Answer: (C)

214.64 in

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

Diameter $=$ radius $\times 2$

Radius, R $=0.25$ in, r $=0.2$ in

$\Rightarrow 303.3=$ $3.14\times (0.25+0.2)\times s$

$\Rightarrow 303.3=$ $3.14\times \left(0.45\right)\times s$

$\Rightarrow \frac{303.3}{3.14}\times 0.45$ $=s$

Slant Height $=s=214.64$ in