document.write( "Question 469583: An artist has 30kg of an alloy that is 45% copper. How many kilograms of a second alloy that is 70% copper should be mixed with the first alloy to get a new alloy that is 60% copper \n" ); document.write( "
Algebra.Com's Answer #322159 by stanbon(75887)\"\" \"About 
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An artist has 30kg of an alloy that is 45% copper. How many kilograms of a second alloy that is 70% copper should be mixed with the first alloy to get a new alloy that is 60% copper
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\n" ); document.write( "Equation:
\n" ); document.write( "copper + copper = copper
\n" ); document.write( "0.45*30 + 0.70x = 0.60(x + 30)
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\n" ); document.write( "Multiply thru by 100 to get:
\n" ); document.write( "45*30 + 70x = 60x + 60*30
\n" ); document.write( "15*30 = 10x
\n" ); document.write( "x = 5 kg (amt of 70% alloy needed)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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