1. 6-8 Scale Drawings

2. Scale Drawing/Model  Used to represent objects too large or too small to be drawn or built in actual size  All measurements are proportional

3. Scale

4. Using Proportions!  The length of a football field is 120 yards. The scale is 1 in = 20 yd. What is the length of the model football field?  Step one: Write the scale as a ratio.  Step two: Fill in what you know. Match up all units!

5. Another Example:  The length of a model airplane is 11.6 inches. The scale is 2 inches for every 15 feet in real life.  What is actual length of the airplane?

6. Another Example:  A scooter is 3.5 feet long. Find the length of a scale model of the scooter if the scale is 1 inch = 24 inches.  hint= you must convert ft to inches.  (12 inches = 1 foot)

7. Scale Factor  A scale written as a ratio without units  Tells how much bigger the actual thing is  Step one: Make both units the same  Step two: Now you can leave off the units  Ex: 1 inch : 3 feet  12 inches = 1 foot…… so …… 3(12) = 36 inches.  1 : 36 … this means the second number is 36 times bigger than the first.

8. Find the scale factor!  Ex: 2 cm to 10 m  Ex: 6 inches to 1 foot  Ex: 2 inches : 15 feet