Question

Find the volume of the right cone shown as a decimal rounded to the nearest tenth.

980.2 m^2
2205.4 m^2
3308.1 m^2
8821.6 m^2

Answer 1

`\huge\boxed{V=2204.3m^3}`

Explanation:

The formula of a volume of a cone:

`V=(1)/(3)\pi r^2H\\\\r-\text{radius}\\H-\text{height}`

We have:

`2r=18m\to r=(18m)/(2)=9m\\\\H=26m`

substitute:

`V=(1)/(3)\pi(9^2)(26)=(1)/(3)(81)(26)\pi=(27)(26)\pi=702\pi(m^3)`

use π ≈ 3.14

`V\approx(702)(3.14)=2204.28(m^3)\approx2204.3`

Answer 2

B

Explanation:

Radius = diameter / 2 = 18/2 = 9 m

Volume = (radius^2 x pi x height)/3 = (9^2 x pi x 26)/3 = 2205.4 m^3