Problema Solution

How many gallons of a 60% antifreeze solution must be mixed with 80 gallons of 20% antifreeze to get a mixture that is 50% antifreeze?

Answer provided by our tutors

G total gallons of 50% mixture is desired

where G = 80 + x


0.6*80 = #gallons of antifreeze in the 60% mixture


(0.6*80 + 0.2*x)/(80+x)=0.5

48+0.2x=40+.5x

.3x=8

x=8/.3=26.667


so add just under 27 gallons of 20% antifreeze