document.write( "Question 903227: How many liters of pure (100%) acid must be added to 20 liters of 30% solution to bring the total solution up to 50% ? \n" ); document.write( "
Algebra.Com's Answer #547857 by stanbon(75887)\"\" \"About 
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How many liters of pure (100%) acid must be added to 20 liters of 30% solution to bring the total solution up to 50% ?
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\n" ); document.write( "Equation:
\n" ); document.write( "acid + acid = acid
\n" ); document.write( "0.30*20 + 1*x = 0.50(20+x)
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\n" ); document.write( "30*20 + 100x = 50*20 + 50x
\n" ); document.write( "50x = 20*20
\n" ); document.write( "x = (2/5)20
\n" ); document.write( "x = 8 liters (amt. of pure acid needed)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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