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Math Help - Two questions sort of.

  1. #1
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    Two questions sort of.

    Would it be right for me to assume X is positive for

    and get to get X =5 as an answer.

    and In Media-eval times there were 10,000 people living in a city that was struck by a plague. the number of people living after 6 days was 8,500 and after 12 days 7,225.
    How would you determine the event is exponential and find the number of people living after 18 days.

    if i set up my chart
    0-10,000
    6-8,500
    12-7,225
    18-X

    I found a common ratio of .85 with help from some one else and after that I got kind of lost. (attempted an equation which didn't work)
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  2. #2
    Master Of Puppets
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    Re: Two questions sort of.

    Firstly, yes x=5

    Plots the points, does it look exp?

    Then consider the model P = P_0 \times A^{kt} where population (P) is a function of time (t).

    It should be clear that P_0 =10000

    Now use the other two points given to find A & k
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  3. #3
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    skeeter's Avatar
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    Re: Two questions sort of.

    don't start another thread by asking the same question in another
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