document.write( "Question 231351: 5. Translate the problem into a pair of linear equations in two vaiables. Solve the equations using either elimination or substitution. State your answer for the specified variable.\r
\n" ); document.write( "\n" ); document.write( "How many liters of a 40%-alcohol solution must be mixed with 10 liters of a solution that is 80% alcohol to get a solution that is 60% alcohol? \n" ); document.write( "

Algebra.Com's Answer #171271 by stanbon(75887) $\"\"$ $\"About$

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How many liters of a 40%-alcohol solution must be mixed with 10 liters of a solution that is 80% alcohol to get a solution that is 60% alcohol?
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\n" ); document.write( "Quantity Eq:: x + 10 = y
\n" ); document.write( "Alcohol Eq:::0.4x + 0.8*10 = 0.6y
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\n" ); document.write( "Rearrange:
\n" ); document.write( "y - x = 10
\n" ); document.write( "0.6y -0.4x = 0.8*10
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\n" ); document.write( "Multiply thru 1st by 6 ; Multiply thru 2nd by 10
\n" ); document.write( "6y - 6x = 60
\n" ); document.write( "6y - 4x = 80
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\n" ); document.write( "Subtract 1st from 2nd to get:
\n" ); document.write( "2x = 20
\n" ); document.write( "x = 10 liters (amt of 40% solution in the mixture)
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\n" ); document.write( "Since y = x+10, y = 20 liters (amt of 60% solution in the mixture)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "

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