Question 953958
Exponential growth model, {{{y=p*e^(kt)}}}.


The description indicates
{{{ln(y)=ln(p)+kt}}}
{{{kt=ln(y)-ln(p)}}}
{{{kt=ln(y/p)}}}
{{{k=ln(y/p)/t}}}
{{{k=ln(3/1)/7}}}
{{{highlight_green(k=ln(3)/7)}}}
The decimal approximation for this is {{{highlight_green(k=0.157)}}}.


Growth Model can be stated, {{{y=p*e^(0.157t)}}}.


You could take as general starting point, p=1 for ALL of any original amount of bacteria;  when 14 hours pass, {{{y(14)=1*e^(0.157*14)}}}, and you already were given that {{{y(7)=1*e^(0.157*7)=3}}}.
Question (a) means, what is {{{1/(y(14))}}}.  You want as percentage.


Find that y(14)=9 which makes sense because you knew that 7 hours was the amount of time to triple in size.