Problema Solution

how many gallons of 40% antifreeze should be mixed with 10 gallons of 85%antifreeze to obtain a 65% antifreeze mixture?

Answer provided by our tutors

Let the amount of 40% mixed = x gallons

total = 10+x gallons

65 = (40x + 850)/(10+x)

=> 650-850 = 40x-65x

=> x = 8 gallons