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Name
Date
Class
Practice B
LESSON
5-8 Scale Drawings and Scale Models
1
The scale of a drawing is 4 in. 15 ft. Find the actual
measurement.
1. 9 in.
2. 12 in.
540 ft
3. 14 in.
720 ft
4. 15 in.
840 ft
900 ft
The scale is 2 cm 25 m. Find the length each measurement
would be on a scale drawing.
5. 150 m
6. 475 m
12 cm
7. 350 m
38 cm
8. 500 m
28 cm
40 cm
Tell whether each scale reduces, enlarges, or preserves the
size of an actual object.
9. 1 m : 25 cm
enlas
10. 8 in. : 1 ft
11. 12 in. : 1 ft
reduces
serves
12. On a map the distance between Atlanta, Georgia, and Nashville,
Tennessee, is 12.5 in. The actual distance between these two
cities is 250 miles. What is the scale?
1 in. 20 mi
1
13. Blueprints of a house are drawn to the scale of 4 in. 1 ft.
A kitchen measures 3.5 in. by 5 in. on the blueprints. What is the
actual size of the kitchen?
14 ft 20 ft
14. A scale model of a house is 1 ft long. The actual house is 50 ft
1
long. In the model, the window is 15 in. high. How many feet
high is the actual window?
5 ft
15. A model of a skyscraper is 1.6 in. long, 2.8 in. wide, and 11.2 in.
high. The scale factor is 8 in. : 250 ft. What are the actual
dimensions of the skyscraper?
50 ft loh
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MSM07G8_RESBK_Ch05_070-086.pe
1/30/06
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Page 85
Practice B
5-8 Scale Drawings and Scale Models
Practice C
5-8 Scale Drawings and Scale Models
LESSON
LESSON
Tell whether each scale reduces, enlarges, or preserves the
size of the actual object.
1
The scale of a drawing is 4 in. 15 ft. Find the actual
measurement.
1. 9 in.
2. 12 in.
540 ft
3. 14 in.
720 ft
1. 1 cm : 1m
4. 15 in.
840 ft
900 ft
6. 475 m
12 cm
7. 350 m
38 cm
enlarges
8. 500 m
40 cm
7. 1 ft model of a 6 in. disk
10. 8 in. : 1 ft
reduces
8. 1 in. model of a 2 ft disk
2:1
1:24
9. 2 ft model of a 10 yd garden
enlarges
6. 3 ft : 1 mi
Change both measurements to the same unit of measure, and
find the scale factor.
Tell whether each scale reduces, enlarges, or preserves the
size of an actual object.
9. 1 m : 25 cm
preserves
5. 1 in. : 2 cm
preserves
28 cm
3. 10 mm : 1 cm
enlarges
4. 3 ft : 1 yd
The scale is 2 cm 25 m. Find the length each measurement
would be on a scale drawing.
5. 150 m
2. 1 ft : 1 in.
reduces
11. 12 in. : 1 ft
reduces
10. 15 in. model of a 750 ft skyscraper
1:15
preserves
1:600
11. Maria’s yard is 40 ft 28 ft 9 in. She made a scale drawing of
her yard that is 16 in. 11.5 in. What is the scale?
12. On a map the distance between Atlanta, Georgia, and Nashville,
Tennessee, is 12.5 in. The actual distance between these two
cities is 250 miles. What is the scale?
2 in. 5 ft
1
12. Blueprints of a house are drawn to the scale of 4 in. 1 ft. A
bedroom measures 4 in. by 5 in. on the blueprints. What is the
actual size of the bedroom?
1 in. 20 mi
1
13. Blueprints of a house are drawn to the scale of 4 in. 1 ft.
A kitchen measures 3.5 in. by 5 in. on the blueprints. What is the
actual size of the kitchen?
16 ft 20 ft
13. The area of a rectangle is 216 ft2. The length of the rectangle is
1
18 ft. If a scale drawing of the figure has a scale of 2 in. 6 ft.
What are dimensions of the rectangle on the scale drawing?
14 ft 20 ft
14. A scale model of a house is 1 ft long. The actual house is 50 ft
1
long. In the model, the window is 15 in. high. How many feet
high is the actual window?
1 in. 1.5 in.
14. A balloon has a diameter of 50 in. The scale factor is 2.54 cm : 1 in.
What is the diameter of the scale model of the ball?
5 ft
15. A model of a skyscraper is 1.6 in. long, 2.8 in. wide, and 11.2 in.
high. The scale factor is 8 in. : 250 ft. What are the actual
dimensions of the skyscraper?
127 cm
1
3
15. A model of a skyscraper is 15 in. long, 15 in. wide, and 16 in.
high. The scale factor is 12 in. : 450 ft. What are the actual
dimensions of the skyscraper?
50 ft long, 87.5 ft wide, 350 ft high
45 ft long, 60 ft wide, 600 ft high
63
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Holt Mathematics
64
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
Holt Mathematics
Challenge
5-8 Too Small, Too Big
Reteach
5-8 Scale Drawings and Scale Models
LESSON
LESSON
A scientist invented a machine that shrinks an object to half its original size.
The pictures below show Spot before he was shrunk and after he was
shrunk 1, 2, and 3 times.
In a scale drawing or a scale model, all the dimensions of the
actual object are reduced or enlarged proportionally.
A map is a scale drawing in which actual distance is reduced.
The towns of Ardon and Bacton are on a map with scale
1 cm 15 km.
If the map distance between Ardon and Bacton
is 4.5 cm, what is the actual distance?
Bacton
actual distance
actual distance
map distance
map distance
15 km
x km
1 cm
4.5 cm
1(x) 15(4.5)
x 67.5 km
2 ft
1. A map scale is 1 in. 75 mi.
The map distance between two
towns is 3.5 in. Find the actual
distance x between the towns.
3
ft
512
共兲
n
1
2 2 ft
The scientist then invented a machine to triple the size of an object.
The pictures below show Spot before his size was tripled and after
being tripled 1, 2, and 3 times.
175 km
7 cm
7x 175
262.5
25
x
262.5 mi
map scale: 1 cm 1
3. An archway in a 2 in. scale drawing
is 4.5 in. tall. Find the actual height x.
2 ft
25 km
4. Under a 7:1 magnification, this letter
F appears to be 84 points high. Find
the actual height x.
actual height
actual height
scale height
scale height
actual height
actual height
scale height
scale height
x ft
1 ft
0.5 in.
4.5 in.
x points
1
7
84 points
0.5x 4.5
x 12
65
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18 ft
54 ft
162 ft; 13,122 ft
5. If you were 6 ft tall and the machine tripled
your size 10 times, how tall would you be?
354,294 ft
6. Write an expression for Spot’s size after he
has been tripled n times.
2 3n ft
2 and 3 are relatively prime so there are no positive integers n and m
3m
such that 2
n 1.
actual height 12 points
9 ft
6 ft
4. How tall would Spot be if he were tripled
1 more time? 5 more times?
7. Could Spot be tripled in size in one machine and then returned to
normal size in the shrinking machine? Explain. Possible answer:
7x 84
x9
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1
1
ft; ft
8
128
3. Write an expression for Spot’s size after he
has been shrunk n times.
x km
1 cm
x mi
75 mi
3.5
in.
1 in.
actual height 1
ft
4
2. If you were 6 ft tall and were shrunk 10 times,
how tall would you be?
2. The actual distance between two
towns is 175 km. If the distance
between them on a map is 7 cm,
what is the map scale?
actual distance
actual distance
map distance
map distance
actual distance 1
ft
2
Ardon
actual distance between Ardon and Bacton
Complete to find each unknown measure.
x
1 ft
1. How tall would Spot be if he were shrunk
1 more time? 5 more times?
Holt Mathematics
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66
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Holt Mathematics