SOLUTION: Please help me solve this word problem: A certain radioactive element decays at a rate of 4% per year. Find the half-life of the substance (i.e. the time it will take for one half

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Question 319971: Please help me solve this word problem: A certain radioactive element decays at a rate of 4% per year. Find the half-life of the substance (i.e. the time it will take for one half of any given amount of the substance to decay).
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Please help me solve this word problem: A certain radioactive element decays at a rate of 4% per year. Find the half-life of the substance
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A(t) = ab^t
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(1/2)a = a(0.96)^t
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(1/2) = (0.96)^t
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Take the log:
t*log(0.96) = log(0.5)
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t = 16.98 years
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Cheers,
Stan H.