Section 10.9

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Section 10.9 Volume Pyramids, Cones, and
Spheres

• pages 566 - 569

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You can fill three cones with sand and pour the
contents into a cylinder with the same height and
radius. You will fill the cylinder evenly to the
top.
The volume of the cone is one third the volume of
the cylinder. The same relationship is true of a
pyramid and a prism with the same base and height
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Volume of a Cone and of a Pyramid
The volume V of a cone or a pyramid is
         the product of the base area B and the
height h.
V ? Bh
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Finding Volume of a Cone
Find the volume of the cone.
The volume of the cone is about 94 ft3.
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Check Understanding
a. Find the volume, to the nearest cubic unit, of
a cone with height 5 cm and a radius of base 2 cm.
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Finding Volume of a Pyramid
Find the volume of the square pyramid.
The volume of the pyramid is 120 ft3.
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Check Understanding
b. Find the volume of a square pyramid that has a
side of 5 ft and a height of 20 ft.
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Volume of a Sphere
V ?r2
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Real-World Problem Solving
Snow Spheres You build a snow statue with snow
spheres. What is the volume of the snow in the
bottom sphere?
The volume of the bottom snow sphere is about 14
ft3.
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Check Understanding
c. Find the volume of a sphere with radius
15 m
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Check Understanding
d. Find the volume of a sphere with diameter 7
mi
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Homework

• pages 568
• s 1-14
• SHOW ALL WORK!
• failure to show work will result in either
  receiving partial or no credit