Pearson Geometry Common Core, 2011
PG
Pearson Geometry Common Core, 2011 View details
Cumulative Standards Review

Exercise 19 Page 758

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

9/2 π m^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 We are told that the circumference is 3 π cm. Let's use the formula for the circumference C of a circle to find the radius r.
C=2Ď€ r
3 π=2π r
3Ď€/2Ď€=r
3/2=r
r=3/2
Let's now substitute 32 for r in the formula for the volume and simplify the right-hand side.
V=4/3Ď€ r^3
V=4/3Ď€ ( 3/2)^3
â–Ľ
Simplify right-hand side
V=4/3Ď€ (3^3/2^3)
V=4/3Ď€ (27/8)
V=4/3(27/8)Ď€
V=108/24Ď€
V=9/2Ď€
The volume of the sphere is 92Ď€ cm^3.