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Radius, diameter, & circumference | Circles (article) | Khan Academy
Learn the relationship between the radius, diameter, and circumference of a circle.
Khan Academy
Explore concepts of radius, diameter, and circumference of circles through engaging video lessons designed for 7th-grade geometry students on Khan Academy.
Radius & diameter from circumference (video) | Khan Academy
Circles are this very fundamental thing in the universe, and you take the ratio of the circumference and the diameter, you get this magical and mystical number that we see that keeps popping …
Radius and diameter (practice) | Geometry | Khan Academy
Practice finding the radius and diameter of a circle using both vocabulary and visuals.
Radius, diameter, circumference & π (video) | Khan Academy
Learn how the number Pi allows us to relate the radius, diameter, and circumference of a circle.
Relating diameter and circumference (video) | Khan Academy
Well, you might do something like maybe take a piece of string, the length of this diameter, and see how many times can you fit it around this circumference. So let's see, you could probably …
Circumference of a circle (practice) | Khan Academy
A circle has a circumference of 113.04 units. What is the diameter of the circle? Use 3.14 for π and enter your answer as a decimal.
Area of a circle (article) | Circles | Khan Academy
Formula for area of a circle Congratulations, you've just shown that when the radius of a circle is r , then the area of a circle is π ⋅ r ⋅ r , which we often write as π r 2 ! If you ever forget this …
Radius and diameter (practice) | Foundations | Khan Academy
Practice finding the radius and diameter of a circle using both vocabulary and visuals.