Big Ideas Math: Modeling Real Life, Grade 8
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Big Ideas Math: Modeling Real Life, Grade 8 View details
3. Volumes of Spheres
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Exercise 2 Page 440

The volume of a sphere is four thirds the product of π and the cube of the radius.

2144.7ft^3

Practice makes perfect

Consider the given sphere.

The volume of a sphere is four thirds the product of π and the cube of the radius. V=4/3π r^3 In the diagram we can see that the diameter is 16 feet. Therefore, the radius is 16÷ 2=8 feet. We can substitute this value for r in the above formula and simplify the right-hand side.
V=4/3π r^3
V=4/3π ( 8)^3
Evaluate right-hand side
V=4/3π (512)
V=4/3(512)π
V=4 * 512/3π
V=2048/3π
V=2144.660585...
V≈ 2144.7
The volume of the sphere, correct to the nearest tenth, is 2144.7 cubic feet.