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See question below. Round your answer to the nearest tenth.

See question below. Round your answer to the nearest tenth.-example-1
User Mike Boutin
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1 Answer

18 votes
18 votes

8.0\:hours

1) In this problem, we must remind that the final amount on the left is half the initial one. Thus, we can plug into that formula the initial amount as 1 and the final 0.5

2) So, let's plug them into the formula:


\begin{gathered} y=y_0e^(-0.086t) \\ \\ 0.5=1\cdot e^(-0.086t) \\ \\ e^(-0.086t)=0.5 \\ \\ \ln \left(e^(-0.086t)\right)=\ln \left(0.5\right) \\ \\ -0.086t=\ln \left(0.5\right) \\ \\ (-0.086t)/(-0.086)=(\ln \left(0.5\right))/(-0.086) \\ \\ t=-(\ln \left(0.5\right))/(0.086) \\ \\ t\approx8.0 \end{gathered}

Thus, the half-life is 8 hours

User Jitendra Yadav
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