Copy of Estimating pi by rolling a circle

Use the blue point to change the circle's diameter. [br]Use the "RollTheCircle" slider to watch the circle roll the distance of one circumference.[br]How does the distance rolled compare with the diameter of the circle?
How does the distance rolled compare with the diameter of the circle?
– Cameron Prince, Duane Habecker

Information: Copy of Estimating pi by rolling a circle