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Annual and daily growth rate

  1. Oct 28, 2004 #1
    Hello, my problem is:

    Let Q(t) = 8(0.87)^t

    Find the annual and daily growth rate.
    Can anyone tell me how to set this up? I don't want you to show me the whole problem, just the 1st step. Thanks a ton!!!
  2. jcsd
  3. Oct 28, 2004 #2
    what units does t have? years?
  4. Oct 29, 2004 #3

    t=months in the equation
  5. Oct 29, 2004 #4
    Ok so how many t in a year? How many t in a day? Just sub those relationships back into the equation and you got your answers.
  6. Oct 29, 2004 #5

    OK, this is what I tried. 8(0.87)^12 and I get 1.50425. I also tried 8(0.87)^(1/12) and I get 7.46. I also tried using 0.13 in replace of 0.87. As you can see, I have tried everything I can think of and tried to manipulate this all I can. Am I using the right numbers? Or, am I setting up the equation incorrectly?
  7. Oct 29, 2004 #6
    Think about how to convert months to years. t months * 1 year/12 months = t years. I hope I didn't lose you when I multiplied by that constant. I'm saying your second formula is right.
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