document.write( "Question 376412: For extremely cold temperatures, an automobile manufacturer recommends that a 80% antifreeze and 20% water mix be used in the cooling system of a car. How many quarts of pure (100%) antifreeze and 50% antifreeze and 50% water mix should be combined to make 11 quarts of 80% antifreeze and 20% water mix? \n" ); document.write( "
Algebra.Com's Answer #267826 by ankor@dixie-net.com(22740)\"\" \"About 
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an automobile manufacturer recommends that a 80% antifreeze and 20% water
\n" ); document.write( " mix be used in the cooling system of a car.
\n" ); document.write( " How many quarts of pure (100%) antifreeze and 50% antifreeze and 50% water
\n" ); document.write( " mix should be combined to make 11 quarts of 80% antifreeze and 20% water mix?
\n" ); document.write( ":
\n" ); document.write( "Let x = amt of pure antifreeze
\n" ); document.write( "Then
\n" ); document.write( "(11-x) = amt of 50% antifreeze required
\n" ); document.write( ":
\n" ); document.write( ".50(11-x) + x = .80(11)
\n" ); document.write( "5.5 - .5x + x = 8.8
\n" ); document.write( ".5x = 8.8 - 5.5
\n" ); document.write( ".5x = 3.3
\n" ); document.write( "Multiply by 2
\n" ); document.write( "x = 6.6 qt of pure antifreeze
\n" ); document.write( "and
\n" ); document.write( "11 - 6.6 = 4.4 quarts of 50% antifreeze
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\n" ); document.write( ":
\n" ); document.write( "Check this in the original equation
\n" ); document.write( ".5(4.4) + 6.6 = .8(11)
\n" ); document.write( "2.2 + 6.6 = 8.8; Confirms our answers \n" ); document.write( "
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