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2 votes
2 votes
A tennis ball can in the shape of a right circular cylinder holds six tennis

balls snugly. If the radius of a tennis ball is 3.2 cm, what percentage of
the can is not occupied by tennis balls?

User GeRyCh
by
3.1k points

1 Answer

17 votes
17 votes

Answer: 33 1/3 percent

Explanation:

First, we need to find the volume of the tennis ball can, which is a cylinder.

The formula for the volume of a cylinder is pi r^2 h.

The radius of a tennis ball is 3.2 cm, so the radius of the cylinder would be 3.2 cm as well.

The height is equivalent to the height of three tennis balls, which is the diameter of 3 tennis balls. The diameter of one tennis ball is 6.4 cm, and we can multiply this by 6 to get 38.4 as our height.

We can plug in these values to our equation for the volume of the cylinder.

pi * 3.2^2 * 38.4

The volume of the cylinder is 393.216 pi.

Now, we need to find the volume of one tennis ball and multiply that by six.

The volume of a sphere is 4/3 pi r^3

We know our radius, 3.2, so we just have to substitute that into the equation.

4/3 pi 3.2^3 = 4/3 * pi * 32.768 = 43.69 and 2/3 pi for the volume of one tennis ball. If we multiply this by six, we get the volume of all the tennis balls, which is 43.6 and 2/3 *3 = 262.144 pi.

Now we have to find the percentage of the cylinder not occupied, so we can find one percent of the container and divide that by 262.144 pi.

1% of 393.216 = 3.93216

262.144 divided by this = 66 and 2/3, so 33 and 1/3 percent of the can is not occupied. The answer depends on how many places to round to, or whether or not to keep the answer as a fraction.

User Cwiggo
by
2.9k points
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