Question

Item 9 Find the surface area of the cone with diameter d and slant height l. Round to the nearest tenth. d=12 cm l=85mm

Answer 1

Answer:
`160.28\ cm^2`

Explanation:

Given

diameter of cone
`d=12\ cm`

radius is
`r=(d)/(2)=6\ cm`

The slant height of the cone
`l=85\ mm\approx 8.5\ cm`

The surface area of a cone is

`\Rightarrow A=\pi rl`

Substitute the value

`\Rightarrow A=(22)/(7)* 6* 8.5=160.28\ cm^2`