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What about this one a tennis ball has a radius of 1.25 inches. The outside of a tennis ball is covered with felt. How many square inches of felt, to the nearest square inch, does it take to cover a tennis ball?

User Tomohiro
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2 Answers

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It takes approximately 20 square inches of felt to cover a tennis ball.

Step-by-step explanation

A tennis ball is in shape of a Sphere. As the outside of the ball is covered with felt, so we need to find the surface area of the ball.

Formula for surface area of sphere:
A= 4\pi r^2

where,
r is the radius of the sphere.

Here the radius is given as 1.25 inch, so
r=1.25

Thus,


A= 4\pi (1.25)^2\\ \\ A= 4(3.14)(1.5625)\\ \\ A= 19.625\\ \\ A= 20 (Approximately)

So, it takes approximately 20 square inches of felt to cover a tennis ball.

User SadSido
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5 votes
The surface area of a sphere is given by the formula
.. A = 4π*r^2
.. A = 4π*(1.25 in)^2 ≈ 20 in^2
User Jwaliszko
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