document.write( "Question 380450: How many liters of a 20% alcohol solution must be mixed with 60 L of a 70% solution to get a 50% solution? \n" ); document.write( "

Algebra.Com's Answer #270019 by stanbon(75887) $\"\"$ $\"About$

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How many liters of a 20% alcohol solution must be mixed with 60 L of a 70% solution to get a 50% solution?
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\n" ); document.write( "Equation:
\n" ); document.write( "alc + alc = alc
\n" ); document.write( "0.20x + 0.70*60 = 0.50(x+60)
\n" ); document.write( "Multiply thru by 100 to get:
\n" ); document.write( "20x + 70*60 = 50x + 50*60
\n" ); document.write( "30x = 20*60
\n" ); document.write( "x = 40 L (amt of 20% solution needed in the mixture)
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\n" ); document.write( "Using 2 equations with 2 variables:
\n" ); document.write( "Quantity Eq: x + 60 = y
\n" ); document.write( "Alcohol Equation: 0.20x + 0.70*60 = 0.50y
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\n" ); document.write( "Substitute for \"y\" in the Alcohol Equation then
\n" ); document.write( "solve as I did using one variable.
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\n" ); document.write( "If this is still confusing let me know.
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\n" ); document.write( "CHeers,
\n" ); document.write( "Stan H. \n" ); document.write( "

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