document.write( "Question 571924: A chemist has two alloys, one of which is 5% gold and 15% lead and the other which is 20% gold and 40% lead. How many grams of each of the two alloys should be used to make an alloy that contains 31 g of gold and 85 g of lead?
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Algebra.Com's Answer #368339 by ankor@dixie-net.com(22740)\"\" \"About 
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A chemist has two alloys, one of which is 5% gold and 15% lead and the other which is 20% gold and 40% lead.
\n" ); document.write( " How many grams of each of the two alloys should be used to make an alloy that contains 31 g of gold and 85 g of lead?
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\n" ); document.write( "Let x = amt of 1st alloy, Let y = amt of the 2nd alloy (in grams)
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\n" ); document.write( "Gold equation: .05x + .20y = 31
\n" ); document.write( "Lead equation: .15x + .40y = 85
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\n" ); document.write( "Multiply the 1st equation by 2, subtract from the 2nd equation
\n" ); document.write( ".15x + .40y = 85
\n" ); document.write( ".10x + .40y = 62
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\n" ); document.write( ".05x + 0y = 23
\n" ); document.write( "x = \"23%2F.05\"
\n" ); document.write( "x = 460 grams of the 1st alloy
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\n" ); document.write( "then using the 1st equation to find y
\n" ); document.write( ".05(460) + .2y = 31
\n" ); document.write( "23 + .2y = 31
\n" ); document.write( ".2y = 31 - 23
\n" ); document.write( "y = \"8%2F.2\"
\n" ); document.write( "y = 40 grams of the 2nd alloy
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\n" ); document.write( "Check these solutions in the 2nd original equation
\n" ); document.write( ".15(460) + .40(40) =
\n" ); document.write( " 69 + 16 = 85\r
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