document.write( "Question 1046116: You need to strengthen a 25% alcohol solution with a pure alcohol solution to obtain a 70% solution. How much pure alcohol should you add to 100 milliliters of the 25% solution? \n" ); document.write( "

Algebra.Com's Answer #661614 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+x+\"$ = ml of pure alcohol to be added
\n" ); document.write( " $\"+.25%2A100+=+25+\"$ ml of pure alcohol in the 25% solution
\n" ); document.write( "-----------------------
\n" ); document.write( " $\"+%28+x+%2B+25+%29+%2F+%28+x+%2B+100+%29+=+.7+\"$
\n" ); document.write( " $\"+x+%2B+25+=+.7%2A%28+x+%2B+100+%29+\"$
\n" ); document.write( " $\"+x+%2B+25+=+.7x+%2B+70+\"$
\n" ); document.write( " $\"+.3x+=+45+\"$
\n" ); document.write( " $\"+x+=+150+\"$
\n" ); document.write( "You need 150 ml of pure alcohol
\n" ); document.write( "--------------
\n" ); document.write( "check:
\n" ); document.write( " $\"+%28+x+%2B+25+%29+%2F+%28+x+%2B+100+%29+=+.7+\"$
\n" ); document.write( " $\"+%28+150+%2B+25+%29+%2F+%28+150+%2B+100+%29+=+.7+\"$
\n" ); document.write( " $\"+175+%2F+250+=+.7+\"$
\n" ); document.write( " $\"+.7+=+.7+\"$
\n" ); document.write( "OK \n" ); document.write( "

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