document.write( "Question 163917: A tank contains 50 gallons of a 40% solution of antifreeze. How much solution needs to be drained out and replaced with pure antifreeze to obtain a 50% solution.\r
\n" ); document.write( "\n" ); document.write( "I really don't know to do this. This is what I think.\r
\n" ); document.write( "\n" ); document.write( "100%=x 50 gallons=x 40% solution=X 50% solution=x\r
\n" ); document.write( "\n" ); document.write( "Let x= amount of pure antifreeze\r
\n" ); document.write( "\n" ); document.write( "x+0.4 (100)= .05(100+x)
\n" ); document.write( "x+4=50+0.5
\n" ); document.write( "x+4=.50(100)+0.4\r
\n" ); document.write( "\n" ); document.write( "I'm lost after this.
\n" ); document.write( " \n" ); document.write( "

Algebra.Com's Answer #120761 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

You can put this solution on YOUR website!
A tank contains 50 gallons of a 40% solution of antifreeze. How much solution needs to be drained out and replaced with pure antifreeze to obtain a 50% solution.
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\n" ); document.write( "Let x = amt of 40% solution removed, and amt of pure antifreeze added:
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\n" ); document.write( ".4(50 - x) + x = .5(50)
\n" ); document.write( ":
\n" ); document.write( "Solve this and you should have it. \n" ); document.write( "

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