Unit 3 Chapter 4 Section 6 Scale Drawings.notebook
December 16, 2015
Please take out your Ch 4 Guided Notes
page 17 and complete the Bell Ringer
Use proportions to solve the following problems:
1) Three gallons of gasoline cost $3.36. How much do 5 gallons cost?
2) At a rate of 50 mph, a car travels a distance of 600 miles. How far will the car travel at a rate of 40 mph if it is driven the same amount of time?
3) If the rent for two weeks is $500, how much is the rent for 5 weeks?
Jul 26­12:38 PM
Dec 15­10:36 AM
Examples:
Unit 3
Chapter 4 Section 6
Scale Drawings
1 cm = 2.5 m
Using a Scale Drawing
1) The length of the side of a house is 3 cm on a scale drawing. What is the actual length of the side of the house? Objective: To use proportions to solve problems involving scale
Scale Drawing : an enlarged or reduced drawing
of an object that is similar to the actual object
drawing drawing
=
actual actual
Scale: the ratio that compares a length in a
drawing or model to the corresponding length in
the actual object
scale =
drawing length corresponding actual length
2) The chimney of the house is 4 cm tall on the drawing. How tall is the chimney of the actual house? 1 cm = 2.5 m
If a 15 foot boat is 1 inch long on a drawing,
you can write the scale of the drawing in the
following ways:
1 in: 15 ft
1 in
15 ft
1 in = 15 ft
Jun 6­8:17 PM
Jun 10­10:28 AM
Finding the Scale of a Model
Application: 3) Refer to the model boxcar shown above. The actual length of a boxcar is 609 in. What is the scale of the model? Write the ratio in simplest form.
scale length =
actual 4) The length of a room in an architectural drawing is 10 in. Its actual length is 160 in. What is the scale of the drawing? Write the ratio in simplest form.
Nov 8­3:36 PM
5) You want to make a scale model of a sailboat that is 51 ft long and 48 ft tall. You plan to make the model 17 in long. Which equation can you use to find x, the height of the model?
a) 48
51
=
17
x
b)
17
51
=
x
48
c)
48
17
= x51
d)
x
17
=
Cross out #6
51
48
Jul 1­12:37 PM
1
Unit 3 Chapter 4 Section 6 Scale Drawings.notebook
December 16, 2015
Finding the Scale of a Map 1
7) The map key shows that a map distance of in. 4
5
represents an actual distance of mi. Find the actual 8
distance represented by 1 in. to write the scale of the map.
9) A model boat is 3.5 ft long. The scale model is 1 ft: 10 ft. What is the actual length of the boat?
map map
=
actual actual
1
4
5
in = mi
8
8) Find the actual distance represented by 1 in. to 2
1
write the scale of a map with a key in = mi.
5
4
Nov 8­3:47 PM
10) A living room is 15 ft wide and 18 ft long. The scale of a floor plan of the house is 1 in : 10 ft. Find the width and the length of the living room on the floor plan. Nov 8­3:53 PM
Challenge
A special­effects artist has made a scale model of a dragon for a movie. In the movie, the dragon will appear to be 16 ft tall. The model is 4 in. tall.
a. What scale has the artist used?
b. The same scale is used for a model of a baby dragon, which will appear to be 2 ft tall. What is the height of the model?
Dec 16­11:42 AM
Jun 26­1:46 PM
Closure
1) 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.
2) An architect's model of a house is 44 in high. The actual house is 20 ft high and 45 ft wide. What should the width of the architect's model be?
3) The scale on a map shows that a map distance 2
4
of in represents an actual distance of mi. Find 5
5
the actual distance represented by 1 in to write the scale of the map.
Jun 10­11:18 AM
Nov 30­1:20 PM
2