document.write( "Question 487016: How many gallons of a 60% antifreeze solution must be mixed with 60 gallons of 25% antifreeze to get a mixture that is 50% antifreeze?\r
\n" ); document.write( "\n" ); document.write( "you need to add ___ gallons of a 60% antifreeze solution.
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Algebra.Com's Answer #332915 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
Let \"+x+\" = gallons of a 60% antifreeze solution needed
\n" ); document.write( "\"+.6x+\" = gallons of antifreeze in the 60% solution
\n" ); document.write( "\"+.25%2A60+=+15+\" = gallons of antifreeze in 25% solution
\n" ); document.write( "--------------
\n" ); document.write( "In words:
\n" ); document.write( "( total gallons of antifreeze ) / ( total gallons of solution ) = 50%
\n" ); document.write( "\"+%28+.6x+%2B+15+%29+%2F+%28+60+%2B+x+%29+=+.5+\"
\n" ); document.write( "\"+.6x+%2B+15+=+.5%2A%28+60+%2B+x+%29+\"
\n" ); document.write( "\"+.6x+%2B+15+=+30+%2B+.5x+\"
\n" ); document.write( "\"+.1x+=+30+-+15+\"
\n" ); document.write( "\"+.1x+=+15+\"
\n" ); document.write( "\"+x+=+150+\"
\n" ); document.write( "150 gallons of 60% antifreeze solution must be added
\n" ); document.write( "check answer:
\n" ); document.write( "\"+%28+.6x+%2B+15+%29+%2F+%28+60+%2B+x+%29+=+.5+\"
\n" ); document.write( "\"+%28+.6%2A150+%2B+15+%29+%2F+%28+60+%2B+150+%29+=+.5+\"
\n" ); document.write( "\"+%28+90+%2B+15+%29+%2F+210+=+.5+\"
\n" ); document.write( "\"+105%2F210+=+.5+\"
\n" ); document.write( "\"+105+=+105+\"
\n" ); document.write( "OK
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