document.write( "Question 981444: You have 80 ml of a 85% alcohol solution. How many mls of a 15% solution must be added to make a 40% solution? \n" ); document.write( "

Algebra.Com's Answer #602427 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+a+\"$ = ml of 15% solution needed
\n" ); document.write( " $\"+.15a+\"$ = ml of alcohol in 15% solution
\n" ); document.write( " $\"+.85%2A80+=+68+\"$ ml of alcohol in 85% solution
\n" ); document.write( "---------------------
\n" ); document.write( " $\"+%28+.15a+%2B+68+%29+%2F+%28+a+%2B+80+%29+=+.4+\"$
\n" ); document.write( " $\"+.15a+%2B+68+=+.4%2A%28+a+%2B+80+%29+\"$
\n" ); document.write( " $\"+.15a+%2B+68+=+.4a+%2B+32+\"$
\n" ); document.write( " $\"+.25a+=+36+\"$
\n" ); document.write( " $\"+a+=+144+\"$
\n" ); document.write( "144 ml of 15% solution are needed
\n" ); document.write( "--------------------------------
\n" ); document.write( "check:
\n" ); document.write( " $\"+%28+.15a+%2B+68+%29+%2F+%28+a+%2B+80+%29+=+.4+\"$
\n" ); document.write( " $\"+%28+.15%2A144+%2B+68+%29+%2F+%28+144+%2B+80+%29+=+.4+\"$
\n" ); document.write( " $\"+%28+21.6+%2B+68+%29+%2F+224+=+.4+\"$
\n" ); document.write( " $\"+89.6+=+.4%2A224+\"$
\n" ); document.write( " $\"+89.6+=+89.6+\"$
\n" ); document.write( "OK \n" ); document.write( "

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