<PRE><B>Question 990824</B>
One alloy contains 80% gold (by weight)and another alloy contains 55% gold.how many grams of each alloy should be combined to make 40g of an alloy that contains 70% gold.
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e = amount of 80%
f = amount of 55%
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e + f = 40  (total alloy)
80e + 55f = 70*40 (total gold)
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