P is the population
x is the time and minutes
the equation of this problem
[tex]P(x)=100000\cdot(\frac{1}{2})^x[/tex]Then we have that P(x)=10, so we need to find the value of x
[tex]10=100000\cdot(\frac{1}{2})^x[/tex]then we need to isolate the x
[tex]\frac{10}{100000}=(\frac{1}{2})^x[/tex][tex]\begin{gathered} In(.0001)=In(\frac{1}{2})^x \\ In(0.0001)=xIn(\frac{1}{2}) \\ x=\frac{In(0.0001)}{In(\frac{1}{2})} \\ x=13.28 \end{gathered}[/tex]It would take 13.28 min for the population of cells to reach 10