<PRE><B>Question 566011</B>
Potassium 42 has a decay rate of approximately 5.5% per hour, assuming an exponential decay model, find the number of hours it will take for the original quantity of potassium 42 to b halved?
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y = ab^x
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(1/2)a = a*b^x
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1/2 = b^x
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1/2 = 0.945^x
x = log(1/2)/log(0.945)
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x = 12.25 years
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Cheers,
Stan H.
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