document.write( "Question 921722: How much pure antifreeze needs to be added to 15 gallons of 40% antifreeze solution to make a 50% solution \n" ); document.write( "

Algebra.Com's Answer #559174 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+x+\"$ = gallons of pure antifreeze to be added
\n" ); document.write( " $\"+.4%2A15+=+6+\"$ gallons of antifreeze in 40% mixture
\n" ); document.write( "-----------------
\n" ); document.write( " $\"+%28+x+%2B+6+%29+%2F+%28+x+%2B+15+%29+=+.5+\"$
\n" ); document.write( " $\"+x+%2B+6+=+.5%2A%28+x+%2B+15+%29+\"$
\n" ); document.write( " $\"+x+%2B+6=+.5x+%2B+7.5+\"$
\n" ); document.write( " $\"+.5x+=+1.5+\"$
\n" ); document.write( " $\"+x+=+3+\"$
\n" ); document.write( "3 gallons of pure antifreeze must be added
\n" ); document.write( "check:
\n" ); document.write( " $\"+%28+x+%2B+6+%29+%2F+%28+x+%2B+15+%29+=+.5+\"$
\n" ); document.write( " $\"+%28+3+%2B+6+%29+%2F+%28+3+%2B+15+%29+=+.5+\"$
\n" ); document.write( " $\"+9+%2F+18+=+.5+\"$
\n" ); document.write( " $\"+.5+=+.5+\"$
\n" ); document.write( "OK \n" ); document.write( "

\n" );