document.write( "Question 566596: How many gallons of 20% alcohol must be mixed with 3 gallons of 70% alcohol to get a mixture that is 30% alcohol \n" ); document.write( "
Algebra.Com's Answer #366285 by Maths68(1474)\"\" \"About 
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Solution A
\n" ); document.write( "Amount =x gallons
\n" ); document.write( "Concentration =20% = 0.2\r
\n" ); document.write( "\n" ); document.write( "Solution B
\n" ); document.write( "Amount = 3 gallons
\n" ); document.write( "Concentration =70% = 0.70\r
\n" ); document.write( "\n" ); document.write( "Resultant Solution
\n" ); document.write( "Amount =(x+3)gallons
\n" ); document.write( "Concentration = 30% = 0.3\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "[Amount Solution A * Concentration A] + [Amount Solution B * Concentration of B] = Amount of Resultant * Concentration of resultant
\n" ); document.write( "(x)(0.2)+(3)(0.7)=(x+3)(0.3)
\n" ); document.write( "0.2x+2.1=0.3x+0.9
\n" ); document.write( "0.2x-0.3x=0.9-2.1
\n" ); document.write( "-0.1x=-1.2
\n" ); document.write( "-0.1x/-0.1=-1.2/-0.1
\n" ); document.write( "x=12\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Solution A
\n" ); document.write( "Amount = x = 12 gallons
\n" ); document.write( "Concentration =20% = 0.2\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "12 gallons of 20% alcohol must be mixed with 3 gallons of 70% alcohol to get a 15 gallons of mixture that is 30% alcohol\r
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