Question $6$

$6$ core samples were taken randomly from a heterogeneous reservoir. The measured absolute permeabilities and porosities are given in the following table:

$\backslash$table$[[$core sample,Porosity $($fraction$),$Permeability $($md$)],[$A$,0\mathrm{.}21,400],[$B$,0\mathrm{.}18,280],[$C$,0\mathrm{.}25,450],[$D$,0\mathrm{.}20,300],[$E$,0\mathrm{.}15,270],[$F$,0\mathrm{.}22,380]]$

Calculate the representative value of the average absolute permeability for the reservoir