document.write( "Question 680217: The problem is: An alloy of metals is 25% copper. Another alloy is 50% copper. How much should be used to make 1000 grams of an alloy that is 45% copper? I am having a problem because in the problem it doesn't state how much is in the first two alloys. \n" ); document.write( "
Algebra.Com's Answer #422341 by ankor@dixie-net.com(22740)\"\" \"About 
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The problem is: An alloy of metals is 25% copper.
\n" ); document.write( " Another alloy is 50% copper.
\n" ); document.write( " How much should be used to make 1000 grams of an alloy that is 45% copper?
\n" ); document.write( ":
\n" ); document.write( "Let x = amt of 50% copper to be used
\n" ); document.write( "then resulting mixture is to be 1000 gr, therefore:
\n" ); document.write( "(1000-x) = amt of 25% copper required
\n" ); document.write( ":
\n" ); document.write( "Write a mixture equation using the decimal equiv
\n" ); document.write( ".50x + .25(1000-x) = .45(1000)
\n" ); document.write( ".50x + 250 - .25x = 450
\n" ); document.write( ".50x - .25x = 450 - 250
\n" ); document.write( ".25x = 200
\n" ); document.write( "x = 200/.25
\n" ); document.write( "x = 800 grams of 50% copper used
\n" ); document.write( ":
\n" ); document.write( "I'll let you find the amt of 25% copper is required \n" ); document.write( "
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