Scale drawing

Proportional Scale Drawings

CLT: Students will understand what scale drawings are from real life examples and will learn how to convert scale drawings from small scale to large scale and large scale to small scale.

Multiple Choice

What is a scale drawing?

• A two-dimensional representation of an actual object or place.

• This line segment from the center of a circle to a point on the circle.

• When two lines cross, they form two pairs of vertical angles across from one another.

• An image that has been made bigger and all the angles change size.

Multiple Choice

Solve the proportion:

• 4

• 8

• 14

• 10

Multiple Choice

Solve the proportion.

• 1

• 3

• 6

• 5

Multiple Choice

Solve the following proportion:

• 34

• 8.5

• 15

• 10

Multiple Choice

Hunter buys 36 baseball cards for $18. How many baseball cards can Troy buy if he has $9?

• 18 baseball cards

• 4 baseball cards

• 24 baseball cards

• 16 baseball cards

What is a scale drawing?

• A scale drawing is a two-dimensional drawing of an object.

• A scale drawing can make the object bigger or smaller.

• The scale gives the ratio of the drawing measurement to the actual measurement. For example, 1 inch : 50 miles.

Example 1

Micah made a scale drawing of their room. In their drawing, 1 cm represents 2 feet. What is the actual length of their room?

Multiple Choice

What is the width of Micha's drawing if the actual width of their room is 15 feet? (Remember the scale is 1 cm/2 ft)

• 6.5 cm

• 30 cm

• 7.5 cm

• 15 cm

Example 2

Kelsey is on a road trip and is reading a map that has a scale of 2 in: 50 miles. Kelsey's trip measures 4.5 inches on the map. What will the actual distance of her trip be?

Fill in the Blanks

What is the distance on the map between Boston and Orlando if they are 1,500 miles apart in real life? (Scale is 2 in: 50 miles)

What is a scale model?

• A scale model is a three-dimensional model of an object.

• A scale model can make the object bigger or smaller.

• The scale gives the ratio of the drawing measurement to the actual measurement. For example, 1 inch : 50 miles.

• Scale models are the 3-D versions of drawings.

Example 3

Mike is building a model of a classic car. The scale is 1 in: 48 in. The actual length of the car is 213.2 inches. How long will the model be?

Multiple Choice

A map has a scale of 1 cm=5km.  On the map, two cities are 3 cm apart. What is the actual distance between these cities? 

• 1.7 km

• 5 km

• 15 km

• 17 km 

Multiple Choice

Find the perimeter of the large triangle.

• 24

• 36

• 12

• 54

Multiple Choice

The two rectangles are scale drawings. What is the measurement of x?

• 21

• 1.25

• 20

• 4

Multiple Choice

Desmond measured a city park and made a scale drawing. The scale he used was 1 centimeter : 9 meters. The actual width of the soccer field is 54 meters. How wide is the field in the drawing?

• 6 cm

• 486 cm

• 9 cm

• 54 cm

Poll

How is the lesson so far?

• Very easy. proceed to next lesson

• I am still confused. but I am getting there

• It is hard. Need more practice.