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Measuring Circles Using the Radius - 2.6.3

Use the slider below and observe what happens. What do you notice? What do you wonder?

About how many radii does it take to go halfway around the circle?

About how many radii does it take to go all the way around the circle?

Why doesn’t the number of radii that fit around the circumference of a circle depend on the length of the radius of the circle?

What is the exact number of radii that fit around the circumference of the circle? Explain how you know. For a hint, type "Give me a hint!" and click "check my answer"

A bicycle wheel has a 1 foot radius. The wheel rolls to the left (counterclockwise).

What is the circumference of the wheel when the radius is 1 foot?