Name
LESSON
Date
Class
Practice A
8-8 Surface Area of Pyramids and Cones
Find the surface area of each figure to the nearest tenth.
1
Pyramid: S B 2 P. Cone: S r 2 r.
Use 3.14 for .
1.
2.
3.
8 cm
6 ft
6 cm
7 cm
4 ft
2 cm
4 ft
6 cm
4.
5.
6.
9m
5 in.
3.2 m
5.5 m
8.4 m
8 in.
9.6 m
7.
8.
8.6 ft
9.
4.2 in.
9 cm
8.5 cm
9 in.
5.2 ft
8.5 cm
5.2 ft
10. Find the surface area of a regular square pyramid with
a slant height of 7 m and a base perimeter of 10 m.
11. Find the length of the slant height of a square pyramid if
one side of the base is 5 ft and the surface area is 125 ft2.
12. Find the length of the slant height of a cone with a radius
of 5 cm and a surface area of 235.5 cm2. Use 3.14 for .
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
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MSM07G8_RESBK_Ch08_065-073.pe
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Page 66
Name
Date
Class
Practice B
LESSON
8-8 Surface Area of Pyramids and Cones
Find the surface area of each figure to the nearest tenth.
Use 3.14 for .
1. 12 ft
2.
3.
24 ft
15 ft
15 cm
12 cm
18 ft
18 ft
9 cm
1017.4 ft
4.
2
13.5 in.
1188 ft
2
5.
423 cm2
16 cm
6.
22.5 in.
13 cm
13 in.
11 cm
1081.7 in2
7.
19.6 in.
527 cm2
8.
15 ft
19.6 in.
1266.2 in2
9.
15.8 m
18 m
22 m
2260.8 m2
16.2 ft
17.9 ft
801.5 ft2
10. Find the surface area of a regular square pyramid with a
slant height of 17 m and a base perimeter of 44 m.
17.6 m
1657.0 m2
495 m2
11. Find the length of the slant height of a square pyramid if
one side of the base is 15 ft and the surface area is 765 ft2.
18 ft
12. Find the length of the slant height of a cone with a radius of
15 cm and a surface area of 1884 cm2.
25 cm
13. A cone has a diameter of 12 ft and a slant height of 20 ft.
Explain whether tripling both dimensions would triple the
surface area. Possible answer:
The surface area of the first cone is 489.84 ft2. The surface area of the
cone with the new dimensions is 4408.56 ft2. It increases the surface
area by a factor of 9.
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
66
Holt Mathematics