SOLUTION: A certain metal is 40% copper. How many kilograms of this metal must be mixed with 80kg of a metal that is 70% copper to get a metal that is 50% copper?
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Question 901166: A certain metal is 40% copper. How many kilograms of this metal must be mixed with 80kg of a metal that is 70% copper to get a metal that is 50% copper? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! A certain metal is 40% copper. How many kilograms of this metal must be mixed with 80kg of a metal that is 70% copper to get a metal that is 50% copper?
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Equation:
copper + copper = copper
0.40x + 0.70*80 = 0.50(x+80)
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40x + 70*80 = 50x + 50*80
-10x = -20*80
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x = 2*80
x = 160 kg (amt of 40% alloy needed)
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Cheers,
Stan H.
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