Question 1101891
Just part (a):


Adding the water does not change AMOUNT of alcohol.


{{{0.6*80/(x+80)=0.4}}}

-

{{{0.6*80=0.4(x+80)}}}

{{{(3/2)(80)=x+80}}}

{{{(3/2)(80)-80=x}}}

{{{x=80(3/2-1)}}}

{{{highlight(x=40)}}}-------liters of water to add