Question

In an alloy of 100 lbs. of zinc and copper there are 75lbs. of copper. How much copper must be added so that the alloy may be 10% zinc?

Answer 1

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Answer 2

I'm working on the percentage

Answer 3

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Answer 4

Cu is the chemical symbol for copper

If the final proportion is to be 10 per cent zinc then it must be 90% copper.

So we make the equation: [Cu / (Cu + 25) ] = .9

Cu = .9Cu + 22.5
.1Cu = 22.5
Cu = 225

We start out with 75 pounds of copper and we need to make it 225 so we have to add 150 pounds of copper.

Answer 5

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