Method #1 – Radius from the volume
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Formula – How to calculate the radius of a sphere from the volume
Radius = 3√((3 x Volume) ÷ (4 x π))
Example
A sphere has a volume of 10
Radius = 3√((3 x 10) ÷ (4 x π))
Radius = 3√((3 x 10) ÷ (4 x 3.14159))
Radius = 3√(30 ÷ 12.56636)
Radius = 3√(2.38733)
Radius = 3√(2.38733)
Radius = 1.33651
Method #2 – Radius from the surface area
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Formula – How to calculate the radius of a sphere from the surface area
Radius = √(Area ÷ 4π)
Example
A sphere has a surface area of 10
Radius = √(10 ÷ (4 x 3.14159))
Radius = √(10 ÷ 12.56636)
Radius = √0.795775
Radius = 0.89206
Method #3 – Radius from the diameter
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Formula – How to calculate the radius of a sphere from the diameter
Radius = Diameter ÷ 2
Example
A sphere has a diameter of 10
Radius = 10 ÷ 2 = 5
Method #4 – Radius from the circumference
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Formula – How to calculate the radius of a sphere from the circumference
Radius = Circumference ÷ π ÷
Example
A sphere has a circumference of 100
Radius = 100 ÷ π ÷ 2
Radius = 100 ÷ 3.14159 ÷ 2
Radius = 15.915508