the half-life of a radioactive substance is the time it takes a given amount of the substance to lose one half of its mass. If the half life of radium is 1690 years, how long does it take to lose 1/3 of its mass??
what is the initial mass to be used?
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Growth and decay 
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Growth and decay
by glaze on Thu Jul 14, 2011 11:21 am
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by stapel_eliz on Thu Jul 14, 2011 12:17 pm
glaze wrote:what is the initial mass to be used?
Whatever value you like. You can use "1" for "100% of whatever you started with", or some random starting value like "100" (or maybe "300" in this case, since then "one-third" would be a hundred).
For explanations and examples, please try here.
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