Circumference. Question 1 Which formula would be best to use to find the diameter of the following circle? C = 81 ft ?

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Presentation transcript:

Circumference

Question 1 Which formula would be best to use to find the diameter of the following circle? C = 81 ft ?

Question 2 Now use the formula you chose to find the diameter (π≈3). Show all work! C = 81 ft ?

Question 3 Find the circumference of the circle shown below (π≈3). Show all work! 7 in.

Question 4 Find the circumference of the circle shown below (π≈3). Show all work! 128 mm

Question 5 What does “pi” mean? Don’t just give the value, explain the reasoning for why we have the value known as pi.

Answer Key 1.C = πd 2.27 feet 3.42 in mm 5.Pi is the ratio of the circumference to the diameter for any circle.