SOLUTION: Melly makes a new alloy out of copper (density of 8.9g/cubic cm)and aluminum (density of 2.6g/cubic centimeter). She puts in 10 more grams of copper than aluminum. The fnal alloy
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-> SOLUTION: Melly makes a new alloy out of copper (density of 8.9g/cubic cm)and aluminum (density of 2.6g/cubic centimeter). She puts in 10 more grams of copper than aluminum. The fnal alloy
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Question 57509: Melly makes a new alloy out of copper (density of 8.9g/cubic cm)and aluminum (density of 2.6g/cubic centimeter). She puts in 10 more grams of copper than aluminum. The fnal alloy has a density of 7g/cubic cm. How much copper did she put in the alloy? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Melly makes a new alloy out of copper (density of 8.9g/cubic cm)and aluminum (density of 2.6g/cubic centimeter). She puts in 10 more grams of copper than aluminum. The final alloy has a density of 7g/cubic cm. How much copper did she put in the alloy?
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Not really sure about this, will treat it like a normal mixture problem
:
Let x = amt of copper: (x-10) = amt of aluminum
Total amt of them added together = (2x-10)
:
8.9x + 2.6(x-10) = 7(2x-10)
8.9x + 2.6x - 26 = 14x - 170
8.9x + 2.6x - 14x = -170 + 26
-2.5x = -44
x = -44/-2.5
x = +17.6 grams of copper
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Check:
7.6 grams of aluminum, Total: 17.6 + 7.6 = 25.2 grams
8.9(17.6) + 2.6(7.6) = 7(25.2)
156.64 + 19.76 = 176.4
