document.write( "Question 190731: Adjusting Antifreeze: Angela needs 20 quarts of 50% antifreeze solution in her radiator. She plans to obtain this by mixing some pure antifreeze with an appropriate amount of a 40% antifreeze solution. How many quarts of each should she use? \n" ); document.write( "
Algebra.Com's Answer #143212 by nerdybill(7384)\"\" \"About 
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Adjusting Antifreeze: Angela needs 20 quarts of 50% antifreeze solution in her radiator. She plans to obtain this by mixing some pure antifreeze with an appropriate amount of a 40% antifreeze solution. How many quarts of each should she use?
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\n" ); document.write( "Let x = quarts of pure antifreeze
\n" ); document.write( "20-x = quarts of 40% antifreeze
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\n" ); document.write( "\"amt of antifreeze from pure\" + \"amt from 40%\" = \"50% of total mixture\"
\n" ); document.write( "x + .40(20-x) = .50(20)
\n" ); document.write( "x + 8 - .40x = 10
\n" ); document.write( "x - .40x = 2
\n" ); document.write( ".60x = 2
\n" ); document.write( "x = 2/.60
\n" ); document.write( "x = 20/6
\n" ); document.write( "x = 10/3 quarts (3.333)
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\n" ); document.write( "Quarts of 40% antifreeze:
\n" ); document.write( "20-x = 20-10/3 = 60/3 - 10/3 = 50/3 quarts (16.667)
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