1. Scale Drawings

2. Scale – The ratio that compares the measurements of the real object and its model. EX: 1 in = 6 ft Scale factor – written as a ratio without measurements and in simplest form EX: the scale factor of 1 in = 6 ft is 1/72

3. Identify the scale factor. ActualModel Length (in.)122 Wing span (in.)183 model length actual length = 2 12 = 1616 Write a ratio using one of the dimensions. Simplify. EX1) EX2) The scale is 1 inch = 3 feet. What is the scale factor? 1 inch 3 feet = To eliminate units convert 3 feet to inches. Conversion factor is 1 foot = 12 inches 1 inch 36 inches 1 36 =

4. = Find the Scale Factor from the following shape 12 3 original Model Original 3 12 Scale factor = 1 4 large small 12 3 Model original large small = Model Original 12 3 Scale factor = 4 1 EX3)

5. A photograph was enlarged and made into a poster. The poster is 20.5 inches by 36 inches. The scale factor is 5. Find the size of the photograph. Think: poster photo = 5151 36 l = 36 X 1= 36 36 ÷ 5 = 7.2 Write a proportion to find the length l and width w. Solve the proportion. Draw a picture. poster photo 20.5 36 l w poster photo = 5151 20.5 w = 20.5 X 1= 20.5 20.5 ÷ 5 = 4.1 EX4) 2. 3. 1.

6. Notes start here

7. Scaling Drawings Date _______

8. Scale – The ratio that compares the _________________ of the _____ object and its _______. EX: 1 in = 6 ft Scale _______ – written as a ratio _______ measurements and in ________________ EX: the scale factor of 1 in = 6 ft is _______

9. Identify the scale factor. ActualModel Length (in.) Wing span (in.) model length actual length = = Write a ratio using one of the dimensions. Simplify. 1 inch 3 feet = To eliminate units convert 3 feet to inches. Conversion factor is __________________ = EX1) EX2) The scale is 1 inch = 3 feet. What is the scale factor?

10. = Find the Scale Factor from the following shape 12 3 original Model Original Scale factor = large small 12 3 Model original large small = Model Original Scale factor = EX3)

11. A photograph was enlarged and made into a poster. The poster is 20.5 inches by 36 inches. The scale factor is. Find the size of the photograph. 5151 Think: poster photo 2. 3. 1. EX4)