document.write( "Question 52688This question is from textbook Intoductory Algebra
\n" ); document.write( ": A metallurgist has one alloy cantaining 20% copper and another containing 70% copper. How many pounds of each alloy must he use to make 50 pounds of a third alloy containing 50% copper?
\n" ); document.write( "Find the equation(s) and solve.
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Algebra.Com's Answer #35167 by funmath(2933)\"\" \"About 
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Let the amount of 20% copper=x
\n" ); document.write( "Then the rest of the mixture would be 70%, let the amount of 70% mixture=50-x
\n" ); document.write( "You multiply percent times amount to get the solutions.
\n" ); document.write( ".20x+.70(50-x)=.50(50) To eliminate the decimals, multiply both sides of the equation by 100 or 10.
\n" ); document.write( "10(.20x)+10(.70)(50-x)=10(.50)(50)
\n" ); document.write( "2x+7(50-x)=5(50)
\n" ); document.write( "2x+350-7x=250
\n" ); document.write( "-5x+350=250
\n" ); document.write( "-5x+350-350=250-350
\n" ); document.write( "-5x=-100
\n" ); document.write( "-5x/-5=-100/-5
\n" ); document.write( "x=20
\n" ); document.write( "The amount of 20% alloy is 20 pounds.
\n" ); document.write( "The amount of 70% alloy is 50-20=30 pounds.
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