document.write( "Question 445611: the cooling system in ann's car contains 19 liters of 30% antifreeze. how much coolant must be drained out and replaced with 80% antifreeze so that the system will contain 50% antifreeze. how much of the original coolant will be left in the car? \n" ); document.write( "
Algebra.Com's Answer #306993 by ankor@dixie-net.com(22740)\"\" \"About 
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the cooling system in ann's car contains 19 liters of 30% antifreeze.
\n" ); document.write( " how much coolant must be drained out and replaced with 80% antifreeze so that
\n" ); document.write( "the system will contain 50% antifreeze?
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\n" ); document.write( "Let x = amt of 80% antifreeze added, this is also the amt of 30% antifreeze removed
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\n" ); document.write( ".30(19-x) + .80x = .50(19)
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\n" ); document.write( "5.7 - .3x + .8x = 9.5
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\n" ); document.write( "-.3x + .8x = 9.5 - 5.7
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\n" ); document.write( ".5x = 3.8
\n" ); document.write( "x = \"3.8%2F.5\"
\n" ); document.write( "x = 7.6 liters of 80% antifreeze added, the same amt of 30% removed
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\n" ); document.write( "how much of the original coolant will be left in the car?
\n" ); document.write( "19 - 7.6 = 11.4 liters of 30% antifreeze remain
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\n" ); document.write( "Check solution
\n" ); document.write( ".3(11.4) + .8(7.6) = 9.5 \n" ); document.write( "
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