document.write( "Question 1030023: how many gallons of a 60% antifreeze solution must be mixed with 60 gallons of 20% antifreeze to get a mixture that is 50% antifreeze? use the 6 step method \n" ); document.write( "

Algebra.Com's Answer #644948 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
I don't know the 6 step method, but
\n" ); document.write( "this is how I do it:
\n" ); document.write( "Let $\"+x+\"$ = gallons of 60% antifreeze solution needed
\n" ); document.write( " $\"+.6x+\"$ = gallons of pure antifreeze in the 60% solution
\n" ); document.write( " $\"+.2%2A60+=+12+\"$ gallons of pure antifreeze in 20% solution
\n" ); document.write( "----------------------------
\n" ); document.write( " $\"+%28+.6x+%2B+12+%29+%2F+%28+x+%2B+60+%29+=+.5+\"$
\n" ); document.write( " $\"+.6x+%2B+12+=+.5%2A%28+x+%2B+60+%29+\"$
\n" ); document.write( " $\"+.6x+%2B+12+=+.5x+%2B+30+\"$
\n" ); document.write( " $\"+.1x+=+18+\"$
\n" ); document.write( " $\"+x+=+180+\"$
\n" ); document.write( "180 gallons of 60% solution are needed
\n" ); document.write( "-----------------
\n" ); document.write( "check answer:
\n" ); document.write( " $\"+%28+.6x+%2B+12+%29+%2F+%28+x+%2B+60+%29+=+.5+\"$
\n" ); document.write( " $\"+%28+.6%2A180+%2B+12+%29+%2F+%28+180+%2B+60+%29+=+.5+\"$
\n" ); document.write( " $\"+%28+108+%2B+12+%29+%2F+240+=+.5+\"$
\n" ); document.write( " $\"+120+=+.5%2A240+\"$
\n" ); document.write( " $\"+120+=+120+\"$
\n" ); document.write( "OK \n" ); document.write( "

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