document.write( "Question 620069: A jeweler has five rings, each weighing 18 grams made of an alloy of 10% silver and 90% gold. He decides to melt down the rings and add enough silver to reduce the gold content to 75%. How much pure silver must be added for the mixture to have a gold content of 75%? \n" ); document.write( "
Algebra.Com's Answer #389908 by ankor@dixie-net.com(22740)\"\" \"About 
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A jeweler has five rings, each weighing 18 grams made of an alloy of 10% silver and 90% gold.
\n" ); document.write( " He decides to melt down the rings and add enough silver to reduce the gold content to 75%.
\n" ); document.write( " How much pure silver must be added for the mixture to have a gold content of 75%?
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\n" ); document.write( "Find the total weight of the rings: 5 * 18 = 90 grams
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\n" ); document.write( "let s = amt of silver required to accomplish this
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\n" ); document.write( ".90(90) = .75(s + 90)
\n" ); document.write( "81 = .75s + 67.5
\n" ); document.write( "81 - 67.5 = .75s
\n" ); document.write( "13.5 = .75s
\n" ); document.write( "s = \"13.5%2F.75\"
\n" ); document.write( "s = 18 grams of silver \n" ); document.write( "
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