Circumference and Area of Circles/Perimeter of Composite Figures

Radius and Diameter

100

Find the radius of image #1. 

10 feet

200

Find the diameter of image #2.

14 meters

300

Find the radius of image #3.

7 feet

400

Find the diameter of image #4.

4 centimeters

500

Find the radius of the small circle in image #5.

11 meters

Formulas

100

The formula for Area of a Circle

A = 𝝅r²

200

Formula for Circumference of a Circle when you have the diameter

C = 𝝅d 

300

Formula for Circumference of a Circle when you have the radius

C = 2𝝅r

400

Formula for Area of a Rectangle (and Square)

A = l x w

500

How to find the perimeter of a Composite Figure (not a "formula")

Add all of the sides together

Perimeter of Composite Figures

100

Find the Perimeter of the Composite Figure in image #6.

16 units

200

Find the Perimeter of the figure in image #7.

32 units

300

Find the Perimeter of the figure in image #8.

29.7 feet

400

Find the Perimeter of the figure in image #9.

56 meters

500

Find the Perimeter of the figure in image #10.

30.26 yards

Area of a Circle

100

Find the Area of image #11.

153.86 cm²

200

Find the Area of image #12.

530.66 in²

300

Find the Area of image #13.

353.25 ft²

400

Find the Area of image #14 rounded to the nearest whole number.

79 units²

500

Find the Area of image #14 if each square has a length of 3 inches.

706.5 in²

Circumference of a Circle

100

Find the Circumference of image #15.

37.68 in

200

Find the Circumference of image #16 rounded to the nearest tenth.

87.9 in

300

Find the perimeter of the semicircular in image #17.

71.96 yd

400

Find the perimeter of the semicircular in image #18.

38.55 ft

500

Image #19 - A coaster has a circumference of 12.56 inches. Suppose the same amount of coaster is visible around the bottom of a glass as shown. What is the circumference of the glass?

9.42 in