Question

A cone has a volume 12 pie cubic inches it’s height 4 inches what is the radius?

Answer 1

The radius of cone is 3 inches.

Explanation:

Given,

Volume of cone = 12π cubic inches

Height of cone = 4 inches

Let,

r be the radius of cone.

Volume of cone =

Multiplying both sides by 3

Dividing both sides by 4π

Taking square root on both sides

The radius of cone is 3 inches.

Keywords: volume, radius

Answer 2

r = 3 in

Explanation:

The formula of a volume of a cone:

`V=(1)/(3)\pi r^2H`

r - radius

H - height

We have V = 12π in³ and H = 4 in. Substitute:

`12\pi=(1)/(3)\pi(r^2)(4)\qquad\text{multiply both sides by 3}\\\\36\pi=4\pi r^2\qquad\text{divide both sides by}\ 4\pi\\\\9=r^2\to r=\sqrt9\to r=3`