Question 46758
{{{A=A[0] e^-0.058t}}}
{{{A=A[0]/2}}}
So:
{{{A[0]/2=A[0] e^-0.058t}}}
Dividing by {{{A[0]}}}:
{{{1/2=e^-0.058t}}}
{{{ln(0.5)=-0.058t}}}
{{{t=-ln(0.5)/0.058}}}
{{{t=11.9508}}} days.


I hope this helps,
Adam
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