document.write( "Question 369696: A goldsmith has 60 pounds of an alloy that is 50% pure gold. How many pounds of an alloy that is 75% pure gold, must be combined with the given 60 pounds of alloy that is 50% pure gold to form an alloy that will be 72% pure gold?\r
\n" ); document.write( "\n" ); document.write( "So far, I have done x+y=72 (not quite sure though if that equation is correct)\r
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Algebra.Com's Answer #263451 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
Let A be the amount of 75% gold.
\n" ); document.write( "Look at the concentrations.
\n" ); document.write( "\"75A%2B50%2860%29=72%28A%2B60%29\"
\n" ); document.write( "\"75A%2B3000=72A%2B4320\"
\n" ); document.write( "\"3A=1320\"
\n" ); document.write( "\"highlight%28A=440%29\"lbs
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