Changes in the Circumference


Nancy Kurtz


What happens to the circumference of a circle if you double the diameter? If you triple the diameter? If you halve the diameter? As the diameter increases (or decreases) in measure, how does the circumference change? Why does this change occur?






My constructions show that as I double, triple, and half my diameter, my circumference changes at the same rate.  The formula for circumference is C=Pi(D) and Pi remains constant as I have shown in my computations.  Since Pi is constant, it would follow that as diameter is changed, the circumference will have to change at the same rate.


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