The video tutorial explains how the perimeter of shapes changes with a scale factor. It uses a rectangle to demonstrate that multiplying the original perimeter by the scale factor gives the new perimeter. This concept is extended to circles, showing that the circumference also changes proportionally with the scale factor. The tutorial verifies these calculations using both formulas and visual drawings.

What happens to the sides of a rectangle when a scale factor of 1.5 is applied?

• The sides double in length.

• The sides become 1.5 times longer.

• The sides remain the same length.

• The sides become 1.5 times shorter.

If the original perimeter of a rectangle is 16, what is the new perimeter after applying a scale factor of 1.5?

• 16

• 32

• 20

• 24

If a rectangle's original perimeter is 16 and the scale factor is 2, what is the new perimeter?

• 32

• 16

• 20

• 24

What is the new perimeter of a rectangle if the original perimeter is 20 and the scale factor is 1.5?

• 20

• 25

• 35

• 30

What is the new perimeter of a rectangle if the original perimeter is 18 and the scale factor is 2?

• 45

• 27

• 36

• 18

How can you calculate the new perimeter of a shape after scaling?

• Add the scale factor to the original perimeter.

• Multiply the original perimeter by the scale factor.

• Subtract the scale factor from the original perimeter.

• Divide the original perimeter by the scale factor.

What is the effect of a scale factor less than 1 on the perimeter of a shape?

• The perimeter remains the same.

• The perimeter decreases.

• The perimeter doubles.

• The perimeter increases.

What is the circumference of a circle with a diameter of 10?

• 10

• 30

• 20

• 40

After applying a scale factor of 1.5 to a circle with a diameter of 10, what is the new diameter?

• 10

• 20

• 12.5

• 15

What is the new circumference of a circle with an original circumference of 30 after a scale factor of 1.5 is applied?

• 45

• 35

• 30

• 40