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What is the approximate surface area of the sphere if circumference is 37.68?

1 Answer

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The surface area of a sphere is A = 4 π R² .

Sadly, the question doesn't give you 'R', so you have to
back it out of the circumference.

Circumference = π (diameter)

Divide each side by π : Diameter = circumference / π

Radius = 1/2 diameter: Radius = circumference / (2 π)

Area = 4 π R² =

4 π (circumference/2π)² =

4 π (circumference)² / 4 π²

Divide top and bottom by 4π : Area = (Circumference)² / π

Circumference = 37.68 units

Area = (37.68)² square units /π =

451.93 square units


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