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Homework Help: Simple log problem

  1. Dec 23, 2005 #1
    If 3150g of a radioactive substance decays to 450g in 73 weeks, determine the half life of the substance to the nearest week. Solve algebraically using logarithms.


    Now, the only problem is the answer says it is 26 weeks. Any help is much appreciated.
  2. jcsd
  3. Dec 23, 2005 #2


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    You're starting with the wrong equation. Try something like

    [tex]450 = 3150 \left( \frac {1}{2} \right)^{73/T}[/tex]

    where T is the half-life.
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