SOLUTION: How many gallons of a 50% antifreeze solution must be mixed with 100 gallons of a 30% antifreeze solution to get a mixture that is 40% antifreeze?

Algebra.Com
Question 729659: How many gallons of a 50% antifreeze solution must be mixed with 100 gallons of a 30% antifreeze solution to get a mixture that is 40% antifreeze?
Answer by checkley79(3341)   (Show Source): You can put this solution on YOUR website!
.50X+.30*100=.40(100+X)
.50X+30=40-.40X
.50X-.40X=40-30
.10X=10
X=10/.10
X=100 GALLONS OF 50% ARE NEEDED.
PROOF:
.50*100+.30*100=.40(100+100)
50+30=.40*200
80=80

RELATED QUESTIONS

How many gallons of 50% antifreeze solution must be mixed with 100 gallons of 30%... (answered by stanbon)
How many gallons of a 60% antifreeze solution must be mixed with 100 gallons of 15%... (answered by stanbon)
how many gallons of a 70% antifreeze solution must be mixed with 100 gallons of 30%... (answered by Tatiana_Stebko)
how many gallons of 60% antifreeze solution must be mixed with 100 gallons of 10%... (answered by jorel1380)
how many gallons of a 60% antifreeze solution must be mixed with 70 gallons of 30%... (answered by jorel1380)
how many gallons of a 60% antifreeze solution must be mixed with 90 gallons of 30%... (answered by stanbon)
How many gallons of an 80% antifreeze solution must be mixed with 100 gallons of 30%... (answered by fcabanski,stanbon)
how many gallons of 50% antifreeze solution must be mixed with 90 gallons of 30%... (answered by scott8148)
How many gallons of 60% antifreeze solution must be mixed with 80 gallons of 30%... (answered by ptaylor)