SOLUTION: A radioactive isotope has a half-life of 14 hours. Find the amount of the isotope left from a 320-milligram sample after 42 hours. If necessary, round your answer to the nearest th

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: A radioactive isotope has a half-life of 14 hours. Find the amount of the isotope left from a 320-milligram sample after 42 hours. If necessary, round your answer to the nearest th      Log On


   

Question 893940: A radioactive isotope has a half-life of 14 hours. Find the amount of the isotope left from a 320-milligram sample after 42 hours. If necessary, round your answer to the nearest thousandth.
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
A radioactive isotope has a half-life of 14 hours. Find the amount of the isotope left from a 320-milligram sample after 42 hours. If necessary, round your answer to the nearest thousandth.
42 = 3*14, 3 half-lives
--> 320*(1/2)*(1/2)*(1/2)
= 40 mg