# Math

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What is the approximate surface area of the sphere? C= 37.68 km

• Math -

C = pi * d

37.68 = 3.14 * d

37.68 / 3.14 = d

12 = d
_____________________________

Surface Area of a Sphere = 4 pi r 2

A = 4 * 3.14 * 6^2

• Math -

Circumference :

C = 2 r pi

C = 2 r pi Divide both sides by 2 pi

C / 2 pi = r

r = C / 2 pi

r = 37.68 / ( 2 * 3.14 =

r = 37.68 / 6.28

r = 6 cm

Area:

A = 4 r ^ 2 pi

A = 4 * 6 ^ 2 * pi

A = 4 * 36 * pi

A = 144 pi

A = 144 * 3.14

A = 452.16 cm ^ 2

• Math -

The area equals 452.16.

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