1. Surface Area and Volume of Pyramids, Cones and Spheres
Sections 12-5, 12-6, 12-7,
13-2, 13-3

2. Surface Area of Pyramids
Surface area = (area of base) + ½ (perimeter of the base)(slant height)
Slant height is the distance up the side of the object 6 8 8

3. Example 1:
The base is an equilateral triangle
10 ft
8 ft

4. Surface Area of Cones
Surface area = area of base + pi(radius)(slant height)
SA= πr2 + πrl l

5. Example 2:
Find the surface area
12m
7.5m

6. Surface Area of Spheres
SA = 4πr2
24 in

7. Volume of Pyramids and Cones
Volume = 1/3(area of the base)(height)
V=(1/3)Bh
Since the base of a cone is a circle,
V=(1/3)πr2h

8. Examples:
Find the volume
7 in
5 in
12 in
3 in
3 in

9. Volume of a Sphere Volume = (4/3)πr3 Find the volume if the
circumference is 25 cm