document.write( "Question 119685: 36 gallons of 25% alchol solution means : 25%, or one quarter, of the solution is pure alchol. one quarter of 36 is 9. That solution contains 9 gallons of pure alchol.\r
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\n" ); document.write( "\n" ); document.write( "how many gallons of 30% alchol solution and how many of 60% alchol solution must be mixed to produce 18 gallons of 50% solution \n" ); document.write( "
Algebra.Com's Answer #87671 by stanbon(75887)\"\" \"About 
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\n" ); document.write( "how many gallons of 30% alchol solution and how many of 60% alchol solution must be mixed to produce 18 gallons of 50% solution
\n" ); document.write( "Let \"x\" be the amount of 30% alcohol; active ingredient = 0.3x gallons
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\n" ); document.write( "Then \"18-x\" is amt. of 60% alcohol ; act. ingre. =0.6(18-x)=10.8-0.6x gals.
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\n" ); document.write( "Amt. of mixture is 18 gals; act. ingre. = 0.5*18 = 9 gallons
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\n" ); document.write( "EQUATION:
\n" ); document.write( "active = active = active
\n" ); document.write( "0.3x + 10.8-0.6x = 9
\n" ); document.write( "-0.3x = -1
\n" ); document.write( "x = 10/3 = 3 1/3 gallons (Amount of 30% alcohol needed for the mixture.)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
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