algebra

A certain country's population P(t), in millions, t years after 1980 can be approximated by P(t) = 2.495(1.019)^t. Find the doubling time.

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  1. solve
    4.990 = 2.495(1.09)^t
    2 = 1.09^t
    log 2 = tlog1.09
    t = log2/log1.09 = 8.043

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  2. 48,6 yr

    58.4 yr

    36.8 yr

    or

    73.7 yr

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  3. I should really have my eyes checked soon, lol
    I saw 1.09 instead of 1.019

    so last line
    t = log2 / log 1.019 = 36.8 years

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