document.write( "Question 781560: A Cooling System In An Automobile Requires 2.5 Gallons Of A 50% Antifreeze Solution. Presently, The Sytem Has A 30% Solution. How Much Of The Present Solution Must Be Replaced With Pure Antifreeze To Bring The System Up To The Recommended Concentration? \n" ); document.write( "
Algebra.Com's Answer #475983 by josgarithmetic(39617)\"\" \"About 
You can put this solution on YOUR website!
Have 30% concentration; want 50% concentration, no change in volume.\r
\n" ); document.write( "\n" ); document.write( "v = volume gallons of the 30% to remove and replace with pure.\r
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\n" ); document.write( "\n" ); document.write( "\"%282.5%2A30-v%2A30%2Bv%2A100%29%2F2.5=50\"------You need to understand this equation.
\n" ); document.write( "\"%282.5%2A30%2B%28100-30%29v%29%2F2.5=50\"
\n" ); document.write( "\"75%2B70v=125\"
\n" ); document.write( "\"70v=125-75\"
\n" ); document.write( "\"v=50%2F70=highlight%285%2F7%29\"\r
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\n" ); document.write( "\n" ); document.write( "Remove \"5%2F7\" of a gallon and replace with pure 100% antifreeze.
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