Question 729751
General form, {{{A(t)=I*e^(-k*t)}}}, I means initial amount, A(t) is amount at time t.


{{{184.8=220*e^(-k*17)}}}
{{{(184.8/220)=e^(-k*17)}}}
{{{0.84=e^(-k*17)}}}
{{{ln(0.84)=-k*17*ln(e)}}}
{{{-(1/17)*ln(0.84)=k}}}
{{{highlight(k=0.01026)}}}


The specific model equation is {{{highlight(A(t)=I*e^(-0.01026*t))}}}.  Half Life is found through {{{1/2=1*e^(-0.01026*t)}}}, and you want to find t.