SOLUTION: hi! can you help me to find the answer? how many gallons of a 50% alcohol solution must be mixed with 40 gallons of an 18% solution to obtain a solution that is 40% alcohol?

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Question 365355: hi! can you help me to find the answer?
how many gallons of a 50% alcohol solution must be mixed with 40 gallons of an 18% solution to obtain a solution that is 40% alcohol?

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
how many gallons of a 50% alcohol solution must be mixed with 40 gallons of an
18% solution to obtain a solution that is 40% alcohol?
:
Let x = amt of 50% solution
:
Write a percent alcohol equation in decimal form
.50x + .18(40) = .40(x+40)
.50x + 7.2 = .40x + 16
.50x - .40x = 16 - 7.2
.10 = 8.8
x = 8.8%2F.1
x = 88 gal of 50% alcohol required to be mixed with 40 gal of 18% alcohol
:
:
Check this:
.5(88) + .18(40) = .4(88+40)
44 + 7.2 = .4(128)
51.2 = 51.2