Question

The diameter of the base of a cone is $10.5\text{cm}$, and its slant height is $10\text{cm}$. What is the curved surface area of the cone?

• A. $165\text{sq cm}$
• B. $180\text{sq cm}$
• C. $177\text{sq cm}$
• D. $150\text{sq cm}$

Answer 1

The correct option is A $165\text{sq cm}$

Diameter =$10.5\text{cm}$, Radius $=\frac{10.5}{2}\text{cm}$
Slant height, $l=10\text{cm}$
Curved surface area of the cone $=\pi rl=\pi \left(5.25\right)\left(10\right){\text{cm}}^2$
$CSA=165{\text{cm}}^2$