Circumference is the outside (perimeter) of a circle. Circumstance is a fact or condition connected with or relevant to an event or action.

Find the circumference of a circle when given either the radius or diameter. Find the radius or diameter of a circle when given the circumference.

What is circumference? Circumference is the distance around the outside of a circle (its perimeter!). Want a review of circle vocabulary terms (like pi, radius, and diameter)? Check out …

Practice Area and circumference of circles challenge Get 3 of 4 questions to level up!

But yes, pi (π) started because mathematicians knew there must exist a constant ratio of a circle's perimeter (we call it circumference) to its diameter (side length but for a circle), just like other …

Just as we said that the circumference could be written as two pi r or as pi times two r, two r is just the diameter. So, we could say that the circumference is equal to pi times the diameter.

Up next for you: Radius and diameter Get 5 of 7 questions to level up! Start Not started Circumference of a circle Get 3 of 4 questions to level up! Practice Not started Area of a circle …

The key here is to realize that from circumference you can figure out radius and then from radius you can figure out area. So we know that circumference, which is six pi, so we know six pi is …

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Learn the relationship between the radius, diameter, and circumference of a circle.