Question 1011650
A goldsmith combined an alloy that costs 430 dollars per gram with an alloy that costs 180 dollars per gram. How many grams of each were used to make a mixture of 200 gram costing 250 dollars per gram? 
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f + n = 200 grams
430f + 180n = 250*200
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Modify for elimination::
430f + 430n = 430*200
430f + 180n = 250*200
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Subtract and solve for "n":
250n = 180*200
n = 144 grams (amt. of $180 alloy needed)
f = 56 grams (amt. of $430 alloy needed)
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Cheers,
Stan H.
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