document.write( "Question 1035980: How many gallons of a 70% antifreeze solution must be mixed with 90 gallons of 25% antifreeze to get a mixture that is 60% antifreeze? Use the six-step method. can you help me do this type proble? \n" ); document.write( "

Algebra.Com's Answer #650573 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
I don't know what the 6-step method is, but
\n" ); document.write( "this is how I do it:
\n" ); document.write( "Let $\"+x+\"$ = gallons of 70% antifreeze needed
\n" ); document.write( " $\"+.25%2A90+=+22.5+\"$ gallons of pure antifreeze in 25% solution
\n" ); document.write( "-----------------------
\n" ); document.write( " $\"+%28+.7x+%2B+22.5+%29+%2F+%28+x+%2B+90+%29+=+.6+\"$
\n" ); document.write( " $\"+.7x+%2B+22.5+=+.6%2A%28+x+%2B+90+%29+\"$
\n" ); document.write( " $\"+.7x+%2B+22.5+=+.6x+%2B+54+\"$
\n" ); document.write( " $\"+.1x+=+31.5+\"$
\n" ); document.write( " $\"+x+=+315+\"$
\n" ); document.write( "315 gallons of 70% antifreeze are needed
\n" ); document.write( "-------------------
\n" ); document.write( "check:
\n" ); document.write( " $\"+%28+.7x+%2B+22.5+%29+%2F+%28+x+%2B+90+%29+=+.6+\"$
\n" ); document.write( " $\"+%28+.7%2A315+%2B+22.5+%29+%2F+%28+315+%2B+90+%29+=+.6+\"$
\n" ); document.write( " $\"+%28+220.5+%2B+22.5+%29+%2F+405+=+.6+\"$
\n" ); document.write( " $\"+243+=+.6%2A405+\"$
\n" ); document.write( " $\"+243+=+243+\"$
\n" ); document.write( "OK \n" ); document.write( "

\n" );