<PRE><B>Question 448243</B>
You can put this solution on YOUR website!
A metallurgist needs to make 12.4 lb of an alloy containing 50% gold. 
He is going to melt and combine one metal that is 60% gold with another metal that is 40% gold. How much of each should he use?
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Equation:
gold + gold = gold
0.60x + 0.40(12.4-x) = 0.50*12.4
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Multiply thru by 100 to get:
60x + 40*12.4 - 40x = 50*12.4
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20x = 10*12.4
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x = 6.2 lb (amt. of 60% alloy needed)
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12.4-x = 6.2 lb (amt. of 40% alloy needed)
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