document.write( "Question 521471: You need a 80% alcohol solution. On hand, you have a 320 mL of a 85% alcohol mixture. How much pure water will you need to add to obtain the desired solution?\r
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Algebra.Com's Answer #346491 by stanbon(75887)\"\" \"About 
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You need a 80% alcohol solution. On hand, you have a 320 mL of a 85% alcohol mixture. How much pure water will you need to add to obtain the desired solution?
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\n" ); document.write( "Equation:
\n" ); document.write( "alcohol + alcohol = alcohol
\n" ); document.write( "0.85*320 + 0*x = 0.80(320+x)
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\n" ); document.write( "Multiply thru by 100 to get:
\n" ); document.write( "85*320 + 0 = 80*320 + 80x
\n" ); document.write( "5*320 = 80x
\n" ); document.write( "x = 20 mL (amt. of pure water needed)
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\n" ); document.write( "Cheers,
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