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The radius of one sphere is twice as great as the radius of a second sphere.

Find the ratio of their surface areas.

  • math -

    4π(2r)^2 / 4πr^2 = 4
    the square of the radius ratio

  • math -

    Find the surface area of an orange with a 3'' radius.

  • math -

    The formula is above. Plug in r=3.

    We will assume a smooth, rather than a dimpled, surface :-)

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