Comparing Ratios of Perimeters and Areas

1
Comparing Ratios of Perimeters and Areas

• Of
• Similar Figures

2
Draw Similar Rectangles ABCD and EFGH whose
lengths and widths are 16 and 12 and 12 and 9
respectively.
3
12
16
9
12
4
Compare the ratio of any two corresponding sides
in simplest form.

• 16/12 4/3

5
Find the Perimeters of each rectangle and express
their ratio in simplest form.

• 56/42 4/3

6
Find the Areas of each rectangle and express
their ratio in simplest form.

• 192/108 16/9

7
Make an observation about the relationship among
the three simplified ratios.

• Corresponding sides..4/3
• Perimeters..4/3
• Areas..16/9

The ratio of the perimeters is equal to the ratio
of the corresponding sides. The ratio of the
areas is equal to the square of the ratio of the
corresponding sides.