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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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