SOLUTION: How much of an alloy that is 20% copper should be mixed with 600 ounces of an alloy that is 70% copper in order to get an alloy that is 30% copper?

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Question 993597: How much of an alloy that is 20% copper should be mixed with 600 ounces of an alloy that is 70% copper in order to get an alloy that is 30% copper?
Answer by htmentor(1343) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = the weight of the 20% alloy
Therefore the total weight of the mixture is x + 600
We can write the following equation which equates the amount of copper from each of the two alloys to the total amount contained in the mixture:
0.2x + 0.7*600 = 0.3(x+600)
Solve for x:
0.1x = = 240
x = 2400 oz
Check:
0.2*2400 + 0.7*600 = 480 + 420 = 0.3(3000) = 900