8th grade math

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Can you please check my answer?

A spherical balloon has a volume of 268 cubic cm. If more air is pumped in so that its radius is 3 times as long, what is its new volume?

My answer: 2,412 cubic cm

  • 8th grade math -

    r^3 Becomes (3r)^3 = 27r^3,

    New Volume = 27 * 268 = 7236 cc.

    ALTERNATE METHOD:

    V = (4/3)3.14*r^3 = 268 cc,
    4.1888r^3 = 268,
    r^3 = 268 / 4.1888 = 63.980,
    r1 = 4.

    New Radius = r2 = 3r1 = 3*4 = 12cm.

    New Volume:

    V = (4/3)3.14*(12)^3,
    V = 4.1867 * 1728 = 7235 CC.

  • 8th grade math -

    6 negative 3

  • 8th grade math -

    i need help

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