Question

How many gallons of a 80% antifreeze solution must be mixed with 60 gallons of 30% antifreeze to get a mixture that is 70% antifreeze?

Answer 1

Let x be the number of gallons.

(x)(80%) + (60)(30%) = (x+60)((70%)

0.8x + 18 = 0.7x +42

0.8x - 0.7x = 42-18

0.1x = 24

and x = 240 Gal.