document.write( "Question 903343: paula has 400 milliliters of a solution that is 80% alcohol. she plans to dilute it so that it is only 50% alcohol. how much water should she add to this? \n" ); document.write( "

Algebra.Com's Answer #547911 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+w+\"$ = ml of water to be added
\n" ); document.write( " $\"+.8%2A400+=+320+\"$ ml of alcohol in 80% solution
\n" ); document.write( "-------------------
\n" ); document.write( " $\"+320+%2F+%28+400+%2B+w+%29+=+.5+\"$
\n" ); document.write( " $\"+320+=+.5%2A%28+400+%2B+w+%29+\"$
\n" ); document.write( " $\"+320+=+200+%2B+.5w+\"$
\n" ); document.write( " $\"+.5w+=+120+\"$
\n" ); document.write( " $\"+w+=+240+\"$
\n" ); document.write( "240 ml of water should be added
\n" ); document.write( "check:
\n" ); document.write( " $\"+320+%2F+%28+400+%2B+240+%29+=+.5+\"$
\n" ); document.write( " $\"+320+%2F+640+=+.5+\"$
\n" ); document.write( " $\"+.5+=+.5+\"$
\n" ); document.write( "OK \n" ); document.write( "

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