Similar Shapes and Scale Models

Which triangle is similar to the above triangle ?

• A

• B

• C

• D

What is the scale factor?

• 4

• 25

What is the measurement of x?

• 21

• 1.25

• 20

• 4

If a Scale Factor is between 0 and 1, then your figure gets...

• Smaller

•  Bigger

• Does not change

If a Scale Factor if greater than 1, then your figure gets...

• Smaller

• Bigger

• Does not change

Joe's picture of a cat was  6 inches by 8 inches.  I copied it.  It is now 3 inches by 4 inches.  My copy is _____________of  the original.  

• ⅙

• ¾

• ¼

• ½

Each pair of shapes are similar. Find the missing surface area.

Each pair of shapes are similar. Find the missing volume.

Two barrels are mathematically similar. It takes 90ml of paint to paint the smaller barrel. How much paint is needed for the larger barrel?

The two circles, A and B, are mathematically similar.
The lengths in B are triple the lengths in A.
The area of A is 15 cm² . Find the area of B.

• 135 cm²

• 145 cm²

• 155 cm²

• 125 cm²