document.write( "Question 98457This question is from textbook Algebra and Trigonometry
\n" ); document.write( ": Please help me with this mixture word problem. A jewel has five rings, each weighing 18 g, 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 silver should he add? I'm having a lot of difficulty with setting up and equation for this particular problem. I would be very thankful if you would help me out. Thank you \n" ); document.write( "
Algebra.Com's Answer #71631 by mathslover(157)\"\" \"About 
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total weight of the rings = 18 * 5 = 90g
\n" ); document.write( "total amount of silver = 10/100 *90 = 9g
\n" ); document.write( "Total amount of gold in all the 5 rings = 90 -9 =81g\r
\n" ); document.write( "\n" ); document.write( "Let the amount of silver added be x grams
\n" ); document.write( "total weight of the mixture now = 90 + x\r
\n" ); document.write( "\n" ); document.write( "percentage of gold = 81/(90+x) *100\r
\n" ); document.write( "\n" ); document.write( "since the percentage of gold now is to be 75 \r
\n" ); document.write( "\n" ); document.write( " 81/(90+x) *100 = 75\r
\n" ); document.write( "\n" ); document.write( "81 * 100 = 75 (90+x)
\n" ); document.write( "27 * (3 * 25) * 4= 75(90+x)
\n" ); document.write( "canceling out 75 on both sided \r
\n" ); document.write( "\n" ); document.write( "27* 4 = 90 +x
\n" ); document.write( "x = 108 -90
\n" ); document.write( " =18g \r
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