document.write( "Question 97708: A nurse has 1 liter of a solution that is 20% alcohol. How much pure alchol must she add to bring the solution up to a 25% concentration \n" ); document.write( "

Algebra.Com's Answer #71087 by stanbon(75887) $\"\"$ $\"About$

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A nurse has 1 liter of a solution that is 20% alcohol. How much pure alcohol must she add to bring the solution up to a 25% concentration
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\n" ); document.write( "20% solution DATA;
\n" ); document.write( "Amt. = 1 liter ; amt of active ingredient = 0.20x liter
\n" ); document.write( "----------------
\n" ); document.write( "100% alcohol DATA;
\n" ); document.write( "Amt. = x liter; amt of active ingredient = x liter
\n" ); document.write( "----------------
\n" ); document.write( "25% Mixture DATA;
\n" ); document.write( "Amt. = (1+x) liter ; amt of active ingredient = 0.25(1+x) = 0.25+0.25x liter
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\n" ); document.write( "EQUATION:
\n" ); document.write( "active + active = active
\n" ); document.write( "0.20x + x = 0.25+0.25x
\n" ); document.write( "1.2x = 0.25 + 0.25x
\n" ); document.write( "0.95x = 0.25
\n" ); document.write( "x = 0.263 liter (amount of pure alcohol that must be added)
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\n" ); document.write( "Cheers, \n" ); document.write( "

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