document.write( "Question 85365: A solution of 79% alcohol is to be mixed with a solution of 20%alcohol to form 413 liters o a 47% solution. How many liters of the 79% solution must be used?
\n" ); document.write( "Thank you so much for helping me. \n" ); document.write( "

Algebra.Com's Answer #61541 by ptaylor(2198) $\"\"$ $\"About$

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Let x=number of liters of the 79% solution needed
\n" ); document.write( "Then 413-x=number of liters of 20% alcohol that must be used\r
\n" ); document.write( "\n" ); document.write( "Now we know that the pure alcohol in the 79% solution (0.79x) plus the amount of pure alcohol in the 20% solution(0.20(413-x)) must equal the amount of pure alcohol in the final mixture (0.47(413)). So our equation to solve is:\r
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\n" ); document.write( "\n" ); document.write( "0.79x+0.20(413-x)=0.47(413) get rid of parens\r
\n" ); document.write( "\n" ); document.write( "0.79x+82.6-0.20x=194.11 subtract 82.6 from both sides\r
\n" ); document.write( "\n" ); document.write( "0.79x+82.6-82.6-0.20x=194.11-82.6 collect like terms\r
\n" ); document.write( "\n" ); document.write( "0.59x=111.51 divide both sides by 0.59\r
\n" ); document.write( "\n" ); document.write( "x=189 liters---------- of the 79% solution is needed\r
\n" ); document.write( "\n" ); document.write( "413-189=224 liters------------------of the 20% solution is needed\r
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\n" ); document.write( "\n" ); document.write( "Ck:\r
\n" ); document.write( "\n" ); document.write( "0.79(189)+0.20(224)=0.47(413)
\n" ); document.write( "149.31+44.8=194.11
\n" ); document.write( "194.11=194.11\r
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\n" ); document.write( "\n" ); document.write( "Hope this helps----ptaylor\r
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