Lesson 2 Activity 3 Worksheet c Table of Contents

Page 2-5 Making a Scale Drawing

Page 6-9 How to Determine a Scale Factor by Applying Ratios

Page 10-12 Scale Practice

Page 13-14 Scale Drawing Activity

Page 15-18 Scale Drawing Practice

Page 19-20 Teacher-Led Scale Drawing Station

Page 21-24 Scale Drawing Extensions

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Name ____________________________________Making a Scale Drawing

For your desk design, you will be required to make a scale drawing of your desk with

two different scales. First, you will need to know the answer to the question “What is a scale?”

A scale drawing is used to represent an object that is too ________________________ to be drawn or built to actual size. It can be a drawing or model that represents a real object such as a house, a map, a poster, or a model airplane.

To solve scale drawing problems, you create a _____________________________ and solve to find the missing information.

Example 1: The scale for a model house is 2in:3ft. If the real house is 21 feet long, how long will the model need to be?

Step 1: Set up your proportion

Step 2: Cross multiply and solve for x.

Example 2: The scale for your house is 2 ft:1 in, your bedroom is 16 feet wide. How long should the drawing be?

Step 1: Set up your proportion

Step 2: Cross multiply and solve for x.

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Let’s try these:

1. On a map, the scale is 1 inch : 150 miles. If the map distance is 3 inches, find the actual distance.

2. Katelyn wants to build a desk for her doll. Her actual desk is 3 feet tall. The scale

is .5 in: 1 ft. How tall will the doll desk be?

3. The length of a stadium is 100 yards and its width is 75 yards.  If 1 inch represents 25 yards, what would be the dimensions of the stadium drawn on a sheet of paper? Hint: You will need to set up 2 proportions.

4. Indirect measurement – You can use proportions to solve indirect measurement problems too. A basketball pole is 10 feet high and cast a 12 foot shadow. A player standing nearby is 5 feet tall. How long is the player’s shadow?

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Name ________________Key____________________Making a Scale Drawing

For your desk design, you will be required to make a scale drawing of your desk with

two different scales. First, you will need to know the answer to the question “What is a scale?”

A scale drawing is used to represent an object that is too large to be drawn or built to actual size. It can be a drawing or model that represents a real object such as a house, a map, a poster, or a model airplane.

To solve scale drawing problems, you create a proportion and solve to find the missing information.

Example 1: The scale for a model house is 2in:3ft. If the real house is 21 feet long, how long will the model need to be?

Step 1: Set up your proportion Formula: scale = scale 2 in = x in actual actual 3 ft 21 ft. Step 2: Cross multiply and solve for x.

3x = 42 3x = 42 x = 14 inches 3 3Example 2: The scale for your house is 2 ft:1 in, your bedroom is 16 feet wide. How long should the drawing be?

Formula: scale = scale 1 in = x in actual actual 2 ft 16 ft.

Cross multiply and solve for x.

2x = 16 x = 8 inches

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Let’s try these: 1. On a map, the scale is 1 inch:150 miles. If the map distance is 3 inches, find the actual

distance.

1 in = 3 in x = 450 mi 150 mi x

2. Katelyn wants to build a desk for her doll. Her actual desk is 3 feet tall. The scale is .5 in: 1 ft. How tall will the doll desk be? 5 in = x 1 ft = 3 ft x = 15 in.

3. The length of a stadium is 100 yards and its width is 75 yards.  If 1 inch represents 25 yards, what would be the dimensions of the stadium drawn on a sheet of paper? Hint: You will need to set up 2 proportions.

1 in = x 1 in = x x = 4 inches 25 yd 75 yd x = 3 inches 25 yd 100 yd

4. Indirect measurement – You can use proportions to solve indirect measurement problems too. A basketball pole is 10 feet high and cast a 12 foot shadow. A player standing nearby is 5 feet tall. How long is the player’s shadow?

10 ft = 5 ft 12 ft x x = 6 ft.

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Name ___________________________________________________

How to Determine a Scale Factor by Applying RatiosWatch the Learn Zillion video on how to determine a scale factor by applying ratios (http://learnzillion.com/lessons/1129-determine-a-scale-factor-by-applying-ratios) and fill out the following notes:

What is a scale factor and how do you compute one?

1. You can determine the scale factor between two similar

figures by _____________________________________________.

2. A ____________________ is a comparison between two

numbers.

3. What is a common mistake people make when creating ratios?

4. Two figures are ______________________ if the lengths of every pair of corresponding sides are in the same

______________________.

5. Fill in the given lengths on the triangles to the right.

6. The _____________________ ______________________.is the

ratio of the lengths of corresponding sides in similar figures.

7. In the map example, the ratio of the scale was inches to miles. What type of scale do you think you should

use for your desk drawing?

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You can use a scale factor to find a missing length.Watch http://learnzillion.com/lessons/1130-find-a-length-by-using-a-scale-factor-and-a-proportion and fill out the following notes:

1. You can calculate actual lengths from a scale drawing by using ______________________ and

______________________.

2. A ______________________ is a comparison of two numbers

3. A ______________________is an equation that relates two equal ratios.

4. What is a common mistake with proportions?

5. You can solve a proportion by ______________________ ______________________.

6. You can also solve a proportion by ______________________ ______________________.

7. Write the proportion given in the video for the model of the Parthenon.

8. Use proportions to find all of the scale drawing dimensions and write in the scale drawing lengths on the drawing to the right:

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Name _______Key____________________________________________How to Determine a Scale Factor by Applying Ratios

Watch the Learn Zillion video on how to determine a scale factor by applying ratios (http://learnzillion.com/lessons/1129-determine-a-scale-factor-by-applying-ratios) and fill out the following notes:

What is a scale factor and how do you compute one?1. You can determine the scale factor between two similar figures by applying ratios.

2. A ratio is a comparison between two numbers.

3. What is a common mistake people make when creating ratios?Reversing the ratio

4. Two figures are similar if the lengths of every pair of corresponding sides are in the same ratio.

5. Fill in the given lengths on the triangles to the right.

6. The scale factor is the ratio of the lengths of corresponding sides in similar figures.

7. In the map example, the ratio of the scale was inches to miles. What type of scale do you think you could use for your desk drawing?

Answers will vary

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You can use a scale factor to find a missing length.Watch http://learnzillion.com/lessons/1130-find-a-length-by-using-a-scale-factor-and-a-proportion and fill out the following notes:

1. You can calculate actual lengths from a scale drawing by using ratios and proportions

2. A ratio is a comparison of two numbers

3. A proportion is an equation that relates two equal ratios?

4. What is a common mistake with proportions? Mixing up the order of one ratio

5. You can solve a proportion by equating ratios

6. You can also solve a proportion by cross multiplying

7. Write the proportion given for the model of the Parthenon.

8. Use proportions to find all of the scale drawing dimensions and write in the scale drawing lengths on the drawing to the right:

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Name ___________________________________________________________Scale Practice

Part 1: Scale FactorDirections: The polygons in each pair are similar. Find the scale factor of the larger figure to the smaller figure.

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Part 2: Missing Side LengthsDirections: The polygons in each pair are similar. Find the missing side length

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Name _________________Key__________________________________________Scale Practice

Key1) 3 : 5 2) 1 : 2 3) 3 : 4 4) 3 : 55) 4 : 5 6) 4 : 5

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Name __________________________________________________

Scale Drawing Activity

You are going to create a scale drawing of one of the provided objects. First, you will need to determine what your scale should be. Then, you are going to create the drawing.

1. First, create a sketch of your object.Sketch of your object:

2. Measure your object. On the sketch, write the actual measurements of your object.

3. Choose your scale. We are drawing it on centimeter-grid paper, so decide what will be equal to 1 cm.

4. Draw your object to scale on the centimeter grid paper. Make sure to write the scale next to your drawing. Write all of your calculations here:

5. Choose another scale for your object. Draw it on the centimeter grid paper. Make sure to write the scale next to your drawing. Write all of your calculations here:

6. Now, choose a scale for your desk drawing and complete the scale portion of the desk challenge worksheet.

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Name _______________________________________________

Scale Drawing Practice

1.

2.

3.

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4.

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Name __________________Key_____________________________

Scale Drawing Practice

1. 22.1 ft.

2.

220m2

3.

5 inches

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4.

96 ft2

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Name _________________________________________

Teacher-Led Scale Drawing Station

1.

2.

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Name ________________Key_________________________

Teacher-Led Scale Drawing Station

1.

10.8 mi

Answers will vary

2.

16.814.4

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Name ____________________________________________

Scale Drawing Extensions

1.

2.Choose any life-sized object. Sketch it and measure its dimensions. Show all work. Then, choose a scale and create a scale drawing on the centimeter grid paper on the back.

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Name ________________Key____________________________

Scale Drawing Extensions

1.

If 1 in = 1.5 ft:6ft by 9ft poster

If 1 in. = 3 ft:12ft. by 18 ft. poster

2.Choose any life-sized object. Sketch it and measure its dimensions. Show all work. Then, choose a scale and create a scale drawing on the centimeter grid paper on the back.

Answers will vary

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