Perimeter and Area with Scale Factor

What is the area ratio of the following rectangles?

• 10/7

• 100/49

• 100/36

• 4/36

The dimensions of a rectangular photo are 3.5 in. x 5 in. The dimensions of the photo are enlarged by a scale factor of 2.5. What is the perimeter of the new photo?

• 17.7 in²

• 8.75 in. X 12.5 in.

• 42.5 in.

• There is not enough information.

If the linear scale factor is 4, what is the area scale factor?

• 2

• 8

• 16

• 25

A scale factor of 1/2 is used to change the dimensions of a rectangle with a length of 7 centimeters and a width of 5 centimeters. What is the perimeter of the resulting rectangle?

• 12

• 35

• 24

• 38

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.

What will be true about this rectangle if you use a scale factor of 1/2 to change the dimensions? Select all that apply.

• The new length is 16 in.

• The new perimeter is 11 in.

• The new perimeter is 21 in.

• The new width is 1.5 in.

• The new length is 4 in.

Which of the following are 2-dimensional measurements? Select all that apply.

• Length of rope

• Volume of a cylinder

• Area of a square

• Area of a triangle

• Perimeter of a rectangle

• The perimeter of the new rectangle will be the same as the perimeter of the original rectangle.
• The perimeter of the new rectangle will be 2.5 times as large as the perimeter of the original rectangle.
• The perimeter of the new rectangle will be 5 times as large as the perimeter of the original rectangle.

If the scale factor is 5, how times larger will the area of the big square be compared to the smaller square?

• 5

• 20

• 25

How does scale factor change the perimeter?

• by the scale factor

• by the scale factor squared

• by the scale factor cubed