Scale Drawings and Maps
11-9
A scale drawing is a drawing of a real
object but is smaller than (a reduction of)
or larger than (an enlargement of) the
object. Measurements on a scale drawing
are proportional to measurements of the
real object.
A scale is a ratio of the scale drawing to
the actual measure. The scale 1 in. 32 ft
on this drawing of a tennis court means
that 1 in. on the drawing represents 32 ft
on the actual tennis court.
3
1
2
in
f
.
t
The scale length of the tennis court is 2 176 in.
What is the actual length of the tennis court?
To find the actual length of the tennis court, n, write
a proportion and use the cross products to solve.
A
S
c
c
t
a
u
l
a
e
l
m
m
e
e
a
a
s
s
u
u
r
r
e
e
A
S
c
c
t
a
u
l
a
e
l
l
l
e
e
n
n
g
g
t
t
h
h
3
1
2
^1 n^32 ^2 1
7
6 n
3
1
(^2)
3
1
9
6 ^78
The actual length of the tennis court is 78 feet.
2 176
n
measure in drawing
actual measuremmi
Scale: 1 in. 32 ft
Copy and complete the table. Use the scale: 1 in. 10 ft.
Rooms Scale Length Scale Width Actual Length Actual Width
Dining Room 1 ^12 in. 1 in.??
Kitchen 1 ^14 in. ^34 in.??
Living Room 2 in. 1 ^34 in.??
2
1
0
3
1
2
in
ft
.
2 176 in.
nft
1.3
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