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Middle School Archive

Browse Middle School Conic Sections/Circles
Stars indicate particularly interesting answers or good places to begin browsing.

Selected answers to common questions:
    Circle formulas - area, circumference.
    Is a circle a polygon?
    Why is a circle 360 degrees?

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What is the Circumference of the Reservoir? [04/09/2003]

John and Tina start running around a round reservoir in opposite directions, meeting for the first time after John has traveled 100 yards, and again 60 yards before Tina has completed her first lap.

What is the difference between these two Pi formulas? [01/30/2001]

To find the circumference of a circle, I know how to use Pi*Diameter and 2*Pi*R, but people have told me about Pi*R*squared. What is that?

Why 6.28 Radians? [10/07/1998]

Why is a circle divided into approximately 6.28 radians?

Why are Manhole Covers Round? [05/09/2000]

Why are most manhole covers round? Why aren't manhole covers on the streets squares or rectangles?

Why Does 1 Degree Equal 60 Minutes? [07/28/2004]

In 60 minutes, the minute hand of a clock makes a full circle, which is 360 degrees. How can 60 minutes equal 1 degree when measuring angles?

Why Is a Circle 360 Degrees? [07/01/1998]

Why is a circle defined as 360 degrees?

Why is Pi a Constant? [08/01/2000]

Why is the circumference of a circle divided by the diameter, or pi, the same number for every circle?

Why Pi? [07/19/2002]

Instead of using pi, why don't we measure the radius and circumference of a given circle, and use that ratio to find the area? Wouldn't that be more accurate?

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