SOLUTION: Okay im not exactly sure what to do here. The half-life of radon-222 is about 85 hours. What fraction of an intial amount of the material would be left afer 10 hours? Thanks fo

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Question 67636: Okay im not exactly sure what to do here.
The half-life of radon-222 is about 85 hours. What fraction of an intial amount of the material would be left afer 10 hours?
Thanks for the help!
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
The half-life of radon-222 is about 85 hours. What fraction of an intial amount of the material would be left afer 10 hours?
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Half-life formula:
A(t) = Ao (1/2)^(t/85)
This formula says the amount of material you will have
after time t is the original amount (Ao) multiplied by (1/2) each time
the total elapsed time is 85 hours.
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For t = 10 hours you get:
A(10) = Ao (1/2)^(10/85)
A(10) = Ao (1/2)^(2/17)
A(10)= Ao [0.92]
The fraction that remains is 92/100 th of the original amount.
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Cheers,
Stan H.