SOLUTION: The function f(x) = 800(.5)^ x/60 models the account in pounds of a particular radioactive material stored in a concrete vault, where X is the number of years since the material wa
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-> SOLUTION: The function f(x) = 800(.5)^ x/60 models the account in pounds of a particular radioactive material stored in a concrete vault, where X is the number of years since the material wa
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Question 1164626: The function f(x) = 800(.5)^ x/60 models the account in pounds of a particular radioactive material stored in a concrete vault, where X is the number of years since the material was put into the vault. Find the amount of radioactive material in the vault after 130 years. Round to the nearest whole number. Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! this is f(x)=800*.5^(130/60)
=178.18 pounds or 178 pounds.
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half-life is 60 years by the formula
this is 2 half-lives and a little more which means that a little more than 3/4 of the material is gone
(3/4) or 800 is 600, so there is a little less than 800-600 or 200 pounds left, which is consistent with the answer.
