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# What is the formula for radius?

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The formula for a radius is the diameter of a circle divided by two. The radius of a circle is defined as the distance from the middle of a circle to any point on the edge of the circle.

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Another way to calculate the radius of a circle is by using the circumference. The equation using the circumference is the circumference of the circle divided by pi times two. Pi (π) is a number that is approximately 3.14. The radius can also be calculated if the area is known; the radius is equal to the square root of the area of the circle divided by pi.

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## Related Questions

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The formula for circumference of a circle is 2πr, where “r” is the radius of the circle and the value of π is approximately 22/7 or 3.14. The circumference of a circle is also called the perimeter of the circle.

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The formula for the area of a circle is pi multiplied by the radius of the circle squared. The radius of the circle is the length of a straight line stretching from the center of the circle to the line of circumference. It is equal to half the diameter.

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The diameter of a circle can be calculated using the formula d = 2r, where "d" indicates the diameter and "r" denotes the radius of the circle. In terms of circumference, the diameter can be computed using the equation d = c/pi, where "c" represents the circumference and pi is approximately equivalent to 3.142. If the area of the circle is given, the formula d = sqrt (4a/pi) can also be used to solve for the diameter, where "a" denotes the area.