Question 1193863
Two points for an exponential function,  (15,100) and (30,1800)


{{{y=ab^x}}}



Use the points:

{{{system(100=ab^15,1800=ab^30)}}}

{{{1800/100=(ab^30)/(ab^15)}}}

{{{18=b^15}}}

{{{b=18^(1/15)}}}

{{{b=1.2125}}}

Using the first equation
{{{ab^15=100}}}
{{{a=100/(b^15)}}}
{{{a=100/(1.2125^15)}}}
{{{a=5.5561}}}


The function as {{{y=5.5561*1.2125^x}}}
but this <b>method may be not the best</b>.  

(Note that the initial bacteria count cannot be between two whole values.)