1. Maps and Scale Drawings
COURSE 2 LESSON 5-7
(For help, go to Lesson 5-4.) 2 3 c 30 52 4 25 5 15 m 13 n = 27 y t 21 9 6 18 x 12
Solve each proportion.
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2. Maps and Scale Drawings
COURSE 2 LESSON 5-7
1. 3x = 24; x = = y = 135; y = = 15
3. 25m = 75; m = = c = 90; c = = 18
5. 18t = 126; t = = n = 52; n = = 1
Solutions 24 3
135 9 75 25 90 5
126 18 52
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3. Maps and Scale Drawings
COURSE 2 LESSON 5-7
Find three integers whose sum is 12 and whose product is 42.
2, 3, 7
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4. Maps and Scale Drawings
COURSE 2 LESSON 5-7
Maps and Scale Drawings
The scale of a drawing is 1 in. : 6 ft. Find the actual length for a drawing length of 4.5 in.
Write the scale of the drawing, 1 in. = 6 ft, as Then write a proportion in which each ratio compares inches to feet.
1 in.
6 ft
Let n represent the actual length.
drawing (in.)
actual (ft) 1 6 =
4.5 n
1n = 6(4.5)
Write cross products.
n = 27
Simplify.
The actual length is 27 ft.
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5. Maps and Scale Drawings
COURSE 2 LESSON 5-7
Maps and Scale Drawings
On a map of North Carolina, the map distance from Asheville to Raleigh would be about 4.4 cm. Find the actual distance from Asheville to Raleigh. The scale on the map is 1 cm : 75 km .
map (cm)
actual (km) 1 75 =
4.4 n
Write a proportion.
1n = 75(4.4)
Write cross products.
n = 330
Simplify.
The actual distance from Asheville to Raleigh is about 330 km.
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6. Maps and Scale Drawings
COURSE 2 LESSON 5-7
Maps and Scale Drawings
The actual length of the wheelbase of a mountain bike is 260 cm. The length of the wheelbase in a scale drawing is 4 cm. Find the scale of the drawing.
scale length
actual length 4
260 = 1 65
Divide each measure by the GCF, 4.
The scale is 1 cm : 65 cm.
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7. Maps and Scale Drawings
COURSE 2 LESSON 5-7
1. The scale of a map is 1 cm : 25 km. Find the actual distance for a map distance of 6.2 cm.
2. The actual length of a machine part is 40 in. The length of the machine part in a scale drawing is 5 in. Find the scale of the drawing.
155 km
1 in. : 8 in.
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