Scale
Drawings
1
I CAN…
Find missing
measurements
using scale
drawings.
2
Vocabulary
 Scale drawing—A drawing that is
similar but either larger or smaller than
the actual object.
 Scale—On a map, intervals used
representing the ratio of distance on the
map to the actual distance.
3
Scale Drawing
Map
1 cm = 4.1 cm
Actual
4.5 km
d
Cross Multiply, then solve.
d = 18.5 km
 The distance on the
map between Coral
Springs and Fort
Lauderdale is about
4.1 cm.
 We can use
proportions to
calculate the actual
distance between the
two locations.
4
 On the map, the
distance
between
Portland and
Olympia is
about 1 7/8
inches.
 What is the
actual distance?
 Remember:
map
actual
5
If the scale on a map of Kentucky reads 1
inch = 4.2 miles, and the distance between
Somerset and Middlesboro on the map
measures 13.5 inches, how many actual
miles apart are they?
6
Vocabulary
 Scale factor—A scale written as a ratio
in simplest form.
 Scale model—A model used to
represent something that is too large or
too small for an actual size model.
7
Find the Scale Factor
1. Find the scale factor of a blueprint if the
scale is 1 inch = 8 feet.
2. On a scale drawing of a new classroom,
the scale is 1 cm = 2.5 m. What is the
scale factor?
8
 Designers are creating a larger
model of the computer memory
board to use in design work. If
they use a scale of 20 inches = 1
inch, what is the length of the
model?
Scale:
Model
actual
Length of Model:
=
model
actual
9
Map Activity
 Using the map of North America, pick a
vacation destination that you would like
to visit.
 Next, using a ruler, measure the distance
in centimeters between Nashville (that is
the nearest airport) and your destination.
 Now you are going to calculate the actual
distance between the two locations.
10
Assignment
 Using grid paper, make a scale drawing
of your ideal bedroom (imagine that you
have won an extreme makeover contest).
 Be sure to use a ruler! You should also
draw furniture that is rectangular in shape
in your room.
 Come up with a scale for your drawing.
 Using your scale, calculate the actual
dimensions of your room (length, width). 11
 Lastly, you are going to write 3-5 quiz
questions regarding your scale drawing.
 Examples:
1. If the scale of my drawing is
1 cm = 4.5m, what is the scale factor?
 Tomorrow you will exchange scale
drawings and questions with a
classmate to test your knowledge!
12
Find the actual distance between each
pair of cities. Round to the nearest tenth
if necessary.
Cities
Map
Distance
Scale
Cities
Map
Distance
Scale
Kokomo,
Indiana and
Chicago,
Illinois
8 cm
1 cm = 25
km
Mobile and
Huntsville,
Alabama
14.5 in
1 in = 20 mi
Raleigh and
Charlotte,
North
Carolina
3.25 in
1 in = 40 mi
19.28 cm
2 cm = 125
km
Virginia
Beach,
Virginia and
Washington,
D.C.
8.5 cm
1 cm = 30
km
Knoxville,
Tennessee
and
Choctaw,
Oklahoma
Quebec,
Canada and
Paris,
France
4.625 in
.5 in = 355
mi
13