1. December 9 6-7 Volume of Pyramids and Cones You will need: Math Notes
Calculator
Pink Formula Sheet
Pencil
Pre-Algebra

2. Volume of Pyramids and Cones
Pre-Algebra
6-7
Volume of Pyramids and Cones
Warm Up
1. Find the volume of a rectangular prism that is 4 in. tall, 16 in. wide and 48 in deep.
2. A cylinder has a height of 4.2 m and a diameter of 0.6 m. To the nearest tenth of a cubic meter, what is the volume of the cylinder?
3072 in3
1.2 m3

3. Learn to find the volume of pyramids and cones.

4. A pyramid is named for the shape of its base
A pyramid is named for the shape of its base. The base is a polygon, and all of the other faces are triangles. A cone has a circular base. The height of a pyramid or cone is measured from the highest point to the base along a perpendicular line.

5. VOLUME OF PYRAMIDS AND CONES
(22)
Remember B = area of base
Fill these in on your pink formula sheet

6. Finding the Volume of Pyramids and Cones
Find the volume of the figure. A. 1 3
V = Bh 1 3 1 2
V = ( · 4 · 7 ) · 6 1 3
V = • 14 • 6
V = 28 cm3

7. Finding the Volume of Pyramids and Cones
Find the volume of the figure. B.
V = Bh 1 3 1 3
V = • (32) • 10 1 3
V = • 9 • 10
V = 30
 94.2 in3

8. Finding the Volume of Pyramids and Cones
Find the volume of the figure. C.
V = Bh 1 3 1 3
V = • (14 • 6) • 10 1 3
V = • 84 • 10
V = 280 m3

9. Finding the Volume of Pyramids and Cones
Find the volume of the figure. A. 1 3
V = Bh
5 in.
7 in. 1 3 1 2
V = ( · 5 · 7 ) · 7 1 3
V = • 17.5 • 7
V = 40.8 cm3

10. Finding the Volume of Pyramids and Cones
Find the volume of the figure. B.
V = Bh 1 3 1 3
V = • (32) • 7
7 m 1 3
V = • 9 • 7
3 m
V = 21
 65.9 in3

11. Try This: Example 1C
Find the volume of the figure. C.
V = Bh 1 3
8 ft 1 3
V = • (4 • 4) • 8
4 ft
4 ft 1 3
V = • 16 • 8
V  42.7 ft3

12. A sphere is the set of points in three dimensions that are a fixed distance from a given point, the center. A plane that intersects a sphere through its center divides the two halves or hemispheres. The edge of a hemisphere is a great circle.

14. Finding the Volume of a Sphere
Find the volume of a sphere with radius 9 cm, both in terms of p and to the nearest tenth of a unit. 4 3
V = pr3
Volume of a sphere
= p(9)3 4 3
Substitute 9 for r.
= 972p cm3
 3,052.1 cm3

15. Try This
Find the volume of a sphere with radius 3 m, both in terms of p and to the nearest tenth of a unit. 4 3
V = pr3
Volume of a sphere
= p(3)3 4 3
Substitute 3 for r.
= 36p cm3
 m3

16. Copy down the homework in your agenda
THEN
Clear your desk and have out a pencil!