Scale Factor Perimeter and Area

If the perimeter of a rectangle was 20in and now it is is 80in, what is the scale factor that was used?

• 4

• 2

• 40

• 20

A rectangle has a perimeter of 15 inches. An image is created with a scale factor of 2. What is the new perimeter?

• 17

• 60

• 30

• 15

A scale factor of 2 is used to enlarge the dimensions of a square. What is the effect of this change on the area of the square?

• The area will be half as big.

• The area will be twice as large.

• The area will be 4 times larger.

• The area will be 8 times larger.

• The area will not change.

When multiplying by a scale factor the area will multiply by...

• The same scale factor

• The scale factor doubled

• The scale factor squared (to the power of 2)

  (scale factor x scale factor)

A figure is multiplied by the scale factor 1/4. What will be the change in area?

• The area will be 1/4 the original area.

• The area will be 1/8 the original area.

• The area will be 1/16 the original area.

If the perimeter is 8 times bigger, what scale factor was used?

• 64

• 8

• 16

• 4

The area of this rectangle is 90 km². If a scaled copy of this rectangle is made using a scale factor of 5, then what is the area of the copy?

• 210 km²

• 450 km²

• 4500 km²

• 2,250 km²

The area of this rectangle is 90 km². If a scaled copy of this rectangle is made using a scale factor of 3, then what is the area of the copy?

• 270 km²

• 810 km²

• 30 km²

• 156 km²

A scale factor greater than one creates ....

• a reduction

• an enlargement

• an exact copy

• none of these

What is the scale factor from ΔDEF to ΔABC?

• 1/2

• 7/3

• 2

• 10/3