Question 727848
2 gallons of fruit punch that is 15% alcohol contains .15*2 = .3 gallons of alcohol.<P>
x gallons of fruit punch that is 20% alcohol contains .2x gallons of alcohol.<P>
The 5 of alcohol in the new mixture is the gallons of alcohol, .2x + .3 divided by the total gallons, x+2.<P>
That fraction, (.2x+.3)/(2+x) = .18.<P>
Solve it for x.<P>
.2x + .3 = .36 + .18x<P>
.02x = .06<P>
x = 3 gallons.
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