GHLesson 77_notes.notebook December 08, 2015

7.7 Scale Drawings and Models

Students will be able to . . .

• interpret scale models.

• use scale factors to solve problems.

Scale Model an object with lengths proportional to the object it represents.

Scale Drawing a drawing with lengths proportional to the object it represents.

Scale the ratio of a length on the model or drawing to the actual length of the object being modeled or drawn

GHLesson 77_notes.notebook December 08, 2015

Example

The distance between Boston and Chicago on a map is 9 inches. The scale of the map is 1 inch : 95 miles.

Determine the actual distance from Boston to Chicago.

Method 1 (proportion)

Scale Boston to Chicago

map

actual=

Method 2 (equation)(actual distance) = scale in miles (map distance) per inch

GHLesson 77_notes.notebook December 08, 2015

Example 2

A miniature replica of a fighter jet is 4 inches long. The actual length of the jet is 12.8 yards.

(a) What is the scale of the model?

(b) How many times as long as the model is the actual jet?

GHLesson 77_notes.notebook December 08, 2015

Practice 77

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