Changing Dimensions Area and Perimeter

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

• The same scale factor

• The scale factor doubled

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

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)

A rectangle has a base 4 ft and height of 5 feet. If the figure dilated by a scale factor of 2, what will be true about its perimeter?

• The perimeter is doubled.

• The perimeter is quadrupled.

• The perimeter is two more.

• The perimeter is four more.

A rectangle has a base 4 ft and height of 5 feet. If the figure dilated by a scale factor of 2, what will be true about its area?

• The area is doubled.

• The area is multiplied by 4.

• The area stays the same

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

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

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

• The perimeter will be 1/16 the original perimeter

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 a spherical ball is enlarged so that its surface area is 9 times greater than its original surface area, then the original radius was multiplied by ____.

• 1

• 3

• 9

• 27

Each edge of pyramid is multiplied by ⅔.  Then the surface area of the new pyramid will be _____ times larger than the original pyramid.

• 2/3

• 3/2

• 4/9

• 8/27

The edges of a cube are all reduced by a factor of ½.  So the surface area will be reduced by a factor of _____.

• ⅛

• ¼

• ½

• ⅙

The surface area of a pyramid is 12 cm².  A new pyramid is similar to the original pyramid and the ratio of the sides of the new to the original is 3:2.  What is the surface area of the new pyramid?

• 12 cm²

• 8 cm²

• 18 cm²

• 27 cm²