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 and effects on area. It also delves into practical applications like scale drawings and maps, providing a comprehensive guide to using scales in geometry.

Which of the following figures is a scaled copy of the original figure A?

• A figure with dimensions 2x3

• A figure with dimensions 3x2

• A figure with dimensions 1x1

• A figure with dimensions 4x4

If a polygon's side length increases from 2.5 to 5, what is the scale factor?

• 0.5

• 1

• 2

• 2.5

What happens to the area of a shape if the scale factor is 3?

• The area triples

• The area becomes nine times larger

• The area remains the same

• The area doubles

How do you find the scale factor if the area of the original polygon is 72 square units and the scaled polygon is 4.5 square units?

• Multiply 72 by 4.5

• Divide 4.5 by 72

• Divide 72 by 4.5

• Multiply 4.5 by 72

If a scale drawing of an aircraft shows a wingspan of 45 feet, what is the approximate actual wingspan if the scale is 1:10?

• 450 feet

• 90 feet

• 45 feet

• 4.5 feet

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

• 10 feet

• 20 feet

• 15 feet

• 12 feet

If a book is 1.5 inches wide on a computer monitor and the actual book is 9 inches wide, what is the scale used?

• 1:6

• 1:5

• 1:4

• 1:3

How long is the actual swimming pool if the scale drawing is 10 cm long and 1 cm represents 1 meter?

• 20 meters

• 10 meters

• 5 meters

• 15 meters

What is the perimeter of quadrilateral Q if it is a scaled copy of quadrilateral P with a scale factor of 3, and P has a perimeter of 62 units?

• 124 units

• 186 units

• 248 units

• 310 units

If a model airplane is built at a scale of 1:72 and the model is 8 inches long, how long is the actual airplane in feet?

• 24 feet

• 36 feet

• 48 feet

• 60 feet