Scale Factors and Proportions

This video tutorial covers the concept of scaled copies, exploring how to identify and create them, calculate scale factors, and understand their relationships. It includes practical applications in drawing and interpreting scale drawings and maps, with a focus on geometry and measurement.

Which of the following figures is a scaled copy of a figure that is 2 units tall and 2 units wide?

• A figure that is 1 unit tall and 1 unit wide

• A figure that is 2 units tall and 3 units wide

• A figure that is 4 units tall and 4 units wide

• A figure that is 3 units tall and 2 units wide

If a polygon has a side length of 2.5 units and its scaled copy has a side length of 5 units, what is the scale factor?

• 2.5

• 2

• 1

• 0.5

What is the perimeter of a scaled copy of a quadrilateral with side lengths 6, 9, 9, and 12, if the shortest side of the copy is 2?

• 14 units

• 12 units

• 10 units

• 8 units

If a right triangle has an area of 36 square units, what will be the area of its scaled copy with a scale factor of 3?

• 108 square units

• 324 square units

• 72 square units

• 144 square units

What is the scale factor used by Diego if the area of polygon P is 72 square units and the area of its scaled version Q is 4.5 square units?

• 1/2

• 1/4

• 1/8

• 1/16

What is the approximate height of the plane when using the scale drawing?

• 12 feet

• 9 feet

• 15 feet

• 10 feet

If a book is 9 inches wide in reality, what is the scale used for its image on a website if the image is 1.5 inches wide?

• 1:12

• 1:9

• 1:6

• 1:3

How does the scale factor affect the perimeter of a scaled quadrilateral?

• It does not affect the perimeter

• It triples the perimeter

• It doubles the perimeter

• It multiplies the perimeter by the scale factor

What is the actual length of a model airplane if the model is 8 inches long and the scale is 1:72?

• 48 feet

• 72 feet

• 36 feet

• 24 feet

If a scale drawing of a swimming pool is 10 cm long and 5 cm wide, what are the actual dimensions if 1 cm represents 1 meter?

• 10 meters long and 5 meters wide

• 15 meters long and 7.5 meters wide

• 20 meters long and 10 meters wide

• 5 meters long and 2.5 meters wide