You drink a beverage with 120 mg of caffeine. Each hour, the caffeine in your system decreases by about 12%. How much caffeine is left in yo

Question

You drink a beverage with 120 mg of caffeine. Each hour, the caffeine in your system decreases by about 12%. How much caffeine is left in your system after 4 hours?

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Trúc Chi 3 years 2021-07-24T09:22:38+00:00 2 Answers 1 views 0

Answers ( )

  1. diemthu
    0
    2021-07-24T09:23:57+00:00
    Reply

    21 hours is probably the best answer

  2. quangkhai
    0
    2021-07-24T09:24:31+00:00
    Reply

    Since the amount if Caffeine decreases by 12% an hour, that is the same as a multiplier of 0.88 per hour.

     

    r = ln 0.88 = -0.117833371

     

    10 = 120 e^-0.117833371t

     

    10/120 =  e^-0.117833371t

     

    0.8333 = 10/120

    ln0.8333 = -2.48490665  so

     

    e^-2.48490665 = e^-0.117833371t    and so

    -2.48490665 = -0.117833371t

    -2.48490665/-0.117833371 = t

    21.08830995 hrs = t

     

    thus 21 hrs is your best answer.

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