HS Calculus/math

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suppose that in any given year, the population of a certain endangered species is reduce by 25%. if the population is now 7500, in how many years will the population be 4000?

  • HS Calculus/math -

    Solve this equation for n, the number of years:

    4000 = 7500 * (0.75)^n

    4000/7500 = 0.5333 = 0.75^n
    n = (log 0.5333)/(log 0.75)

    It will take a bit more than 2 years.

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