Growth and decay

Limits, differentiation, related rates, integration, trig integrals, etc.
glaze
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Growth and decay

Postby glaze » Thu Jul 14, 2011 11:21 am

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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stapel_eliz
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Postby stapel_eliz » 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. :wink:

glaze
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Re: Growth and decay

Postby glaze » Mon Jul 18, 2011 3:13 pm

thank you so much! God bless you!


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