Real World Application 1) 882.75 107.5 11.25 wide Width of Titanic 882.75ft w Length of Titanic = 11.25in. 107.5in. Width of model ship Length of model ship

1) How wide is the Titanic? Example 1) How wide is the Titanic? w 882.75ft 11.25 in. 107.5 in. = w  107.5 112.25  882.75 107.5w = 9930.9375 107.5 107.5 107.5 w = 92.4 feet

Lesson Objectives 1) Use scale drawings to find actual distances. 2) Find scale factors. 3) Use scale drawings to find actual perimeters and areas. 4) Recreate scale drawings at a different scale.

Definition Scale drawing - a drawing that uses a scale to make an object smaller than or larger than the real object.

Example If two figures are similar, one figure is an enlargement of the other. The size-change (scale) factor tells the amount of enlargement or reduction. If a copy machine is used to copy a drawing or picture, the copy will be similar to the original. Original Copy Copy Original Copy Original Copy Exact Copy Exact Copy Exact Copy Copy machine set to 100% (scale) factor is Copy machine set to 200% (scale) factor is Copy machine set to 50% (scale) factor is 1 2 X 1X 2X

Definition Consider Dr. Evil and Mini Me from Mike Meyers’ hit movie Austin Powers. Mini Me is supposed to be an exact replica of Dr. Evil.

Definition Scale - the ratio between two sets of measurements. One of them usually is a 1. 3 in 1 in 3 in 1 in Model(new) length 3 in = Actual length 1 in

Example 2) Identify the scale factor. 72 6 36 3 1 in 6 3 1 in = = 72 The scale factor is . 12 in

Whiteboard Practice 3) Identify the scale factor. 11.5 3 42 12 6 in 3 = = 11.5 23 in 42 3.5 in 1 in The scale factor is . 3.5 in

Whiteboard Practice 4) Identify the scale factor. 60 10 10 1 in = 60 The scale factor is . 6 in

Whiteboard Practice 5) Identify the scale factor. 56 1 in = 56 112 in The scale factor is . 112 in

Example 4 = d 52 6) 1 13 centimeters 1 Map distance 1 13 d d = = Actual distance 13 52 52 = 1  52 13  d 4 = d 52 = 13d The distance is 4 cm on the map. 13 13 13

The scale of the spaceship is 1 inch = 26 feet. Example 7) 156 6 scale Drawing height 6 in ÷ 6 1 in = = 6 Actual height 156ft 26 ft ÷ The scale of the spaceship is 1 inch = 26 feet.

Whiteboard Practice 10 = d 8) 5 1 2 kilometers Map distance 1 2 5 5 = = Actual distance 2 d d = 1  d 2  5 10 = d The obstacles course is 10 km long.

The scale of the skateboard ramp is 1 inch = 9 inches. Whiteboard Practice 9) 36 4 scale Drawing height 4 in ÷ 4 1 in = = 4 Actual height 36 in 9 in ÷ The scale of the skateboard ramp is 1 inch = 9 inches.

The scale of the tank is 1 inch = 4.4 feet. Whiteboard Practice 10) 22 5 scale Model Length 5 in ÷ 5 1 in = = 5 Actual Length 22 ft 4.4 ft ÷ The scale of the tank is 1 inch = 4.4 feet.

Whiteboard Practice 2 = d 11) 34 1 17 centimeters 1 Map distance 1 17 Actual distance 17 34 34 = 1  34 17 d 2 = d 34 = 17d Andrea is moving 2 cm away on the map. 17 17 17

The actual playground is 48 yards. Whiteboard Practice 12) 1 8 6 actual 1 Drawing distance 1 8 6 6 = = Actual distance 8 d d = 1  d 8  6 d = 48 The actual playground is 48 yards.

The scale of the whale is 1 inch = 7 feet. Whiteboard Practice 13) 56 8 scale Drawing height 8 in ÷ 8 1 in = = 8 Actual height 56 ft 7 in ÷ The scale of the whale is 1 inch = 7 feet.

Example d = 36 14) 1 2 18 actual 1 Drawing distance 2 1 18 18 = = Actual distance 2 d d = 1  d 2  18 d = 36 36ft

Example d = 78 14) 1 2 39 actual 1 Drawing distance 2 1 39 39 = = Actual distance 2 d d = 1  d 2  39 78ft d = 78 36ft

Example Area = L  W Area = 78ft  36ft Area = 2,808 ft2 14) Area = Perimeter = Area = 78ft  36ft 78ft 78ft Area = 2,808 ft2 36ft 36ft

Example 14) Area = 2,808 ft2 Perimeter = 228 ft Perimeter = Add up all sides 36ft 36ft Perimeter = 78 + 36 + 78 + 36 78ft 78ft 78ft 78ft 36ft 36ft Perimeter = 228 ft

Whiteboard Practice d = 84 15) 1 4 21 actual 1 Drawing distance 4 1 21 Actual distance 4 d d = 1  d 4  21 d = 84 84ft

Whiteboard Practice d = 164 15) 1 4 41 actual 1 Drawing distance 4 1 Actual distance 4 d d = 1  d 4  41 164ft d = 164 84ft

Whiteboard Practice Area = L  W Area = 164ft  84ft Area = 13,776 ft2 15) Area = 13,776 ft2 Area = L  W Perimeter = Area = 164ft  84ft 164ft 164ft Area = 13,776 ft2 84ft 84ft

Whiteboard Practice 15) Area = 13,776 ft2 Perimeter = 496 ft Perimeter Add up all sides 84ft 84ft Perimeter = 164 + 84 + 164 + 84 164ft 164ft 164ft 164ft 84ft 84ft Perimeter = 496 ft

Whiteboard Practice d = 2 16) 1 2 1 actual 1 Drawing distance 2 1 1 1 Actual distance 2 d d = 1  d 2  1 d = 2 2ft

Whiteboard Practice d = 18 16) 1 2 9 actual 1 Drawing distance 2 1 9 9 Actual distance 2 d d = 1  d 2  9 18ft d = 18 2ft

Whiteboard Practice Area = L  W Area = 18ft  2ft Area = 36 ft2 16) Perimeter = Area = 18ft  2ft 18ft 18ft Area = 36 ft2 2ft 2ft

Whiteboard Practice 16) Area = 36 ft2 Perimeter = 40 ft Perimeter = Add up all sides 2ft 2ft Perimeter = 18 + 2 + 18 + 2 18ft 18ft 18ft 18ft 2ft 2ft Perimeter = 40 ft

Key Points & Don’t Forget 1) Write the ratio out in words before you start the problem. 2) Scale is the new divided by the original.

Bibliography