Math

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The circumference of a circle is 4 times the circumference of a circle with a radius 1 unit less. What is the radius of each circle?

  • Math -

    radius of larger circle --- r
    radius of smaller circle --- r-1

    circumf of large ---- 2πr
    circumf of smaller = 2π(r-10

    but 2πr = 4(2π(r-1))
    2πr = 8πr - 8π
    divide each term by π and rearrange equation
    -6r = -8
    r = 8/6 = 4/3

    larger has radius 4/3
    smaller has radius 1/3

    I will leave the checking up to you,

  • Math -

    HATS OFF ! Amazing is a less adjective for you. Thank you.

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