Finding the Circumference of a Circle - Math by...

1
Math by Design Hint Pages Copyright Maryland Public Television 2009, Local Service Initiative http://mathbydesign.thinkport.org Finding the Circumference of a Circle Windjammer Center, Slam Dunk Task: Paint the lines. Vocabulary: The formula for finding the Circumference of a circle is: C = πd where d represents the diameter of the circle. The formula may also be written: C = 2πr where r is the radius of the circle. Example 1: The diameter of a circle is 16 cm. Find the circumference of the circle. ( cm) 50.2 16 7cm C d C C = π Answer: The circumference of the circle is approximately 50.27 cm. Example 2: The radius of a circle is 16 cm. Find the circumference of the circle. 2 2( cm) 16 100.53 cm C r C C = π = π Answer: The circumference of the circle is approximately 100.53 cm. Circumference Center of Circle Diameter Radius

Transcript of Finding the Circumference of a Circle - Math by...

Page 1: Finding the Circumference of a Circle - Math by Designmathbydesign.thinkport.org/images/pdfs/Hint_CircumferenceofCircle.pdf · Title: Finding the Circumference of a Circle Author:

Math by Design Hint Pages

Copyright Maryland Public Television 2009, Local Service Initiative http://mathbydesign.thinkport.org

Finding the Circumference of a Circle Windjammer Center, Slam Dunk Task: Paint the lines. Vocabulary: The formula for finding the Circumference of a circle is: C = πd where d represents the diameter of the circle. The formula may also be written: C = 2πr where r is the radius of the circle. Example 1: The diameter of a circle is 16 cm. Find the circumference of the circle.

( cm)50.2

167cm

C dCC

= π= π≈

Answer: The circumference of the circle is approximately 50.27 cm. Example 2: The radius of a circle is 16 cm. Find the circumference of the circle.

22 ( cm)16100.53cm

C rCC

= π= π≈

Answer: The circumference of the circle is approximately 100.53 cm.

Circumference

Center of Circle

Diameter

Radius