Question

A vendor at a street fair sells popcorn in cones, all of height 9 inches. The
sharing-size cone has 3 times the radius of the skinny-size cone. About how
many times more popcorn does the sharing cone hold than the skinny cone?

Answer 1

Answer:

The sharing cone holds about 9 times more popcorn than the skinny cone.

Step-by-step explanation:

The volume of a cone is given by the following formula:

$V = \frac{\pi r^{2}h}{3}$

In which r is the radius and h is the height.

Two cones:

Both have the same height.

The sharing-size cone has 3 times the radius of the skinny-size cone.

Skinny:

radius r, height h. So

$V_{sk} = \frac{\pi r^{2}h}{3}$

Sharing size:

radius 3r, height h. So

$V_{sh} = \frac{\pi (3r)^{2}h}{3} = \frac{9\pi r^{2}h}{3} = 3\pi r^{2}h$

About how many times more popcorn does the sharing cone hold than the skinny cone?

$r = \frac{V_{sh}}{V_{sk}} = \frac{3\pi r^{2}h}{\frac{\pi r^{2}h}{3}} = \frac{3*3\pi r^{2}h}{\pi r^{2}h} = 9$

The sharing cone holds about 9 times more popcorn than the skinny cone.