PreCalculus

A lake formed by a newly constructed dam is stocked with 1,000 fish. Their population is expected to increase according to the logistic curve
N=30/(1+29e^-1.35t)
where N is the number of fish, in thousands, expected after t years. The lake will be open to fishing when the number of fish reaches 20,000. How many years, to the nearest year, will this take?

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asked by Terri
  1. well, just solve for t:

    20 = 30/(1+29e^-1.35t)
    1+29e^-1.35t = 1.5
    e^-1.35t = 0.5/29
    -1.35t = -4.060
    t = 3

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    posted by Steve

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