What is the ratio of a circle of radius 3 units? How about with radius 7 units? What about radius 2.34 units?

After exploring this ratio we can conclude that:

All circles have r = 4*pi = 12.56

How does this come about?

• The perimeter of a circle is circumference of 2*(pi)*radius.
• Perimeter squared is....4*(pi^2) * radius^2
• Area is pi * radius^2
• So the ratio=4*pi after cancelling.
• Do it yourself and see why.....

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