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An alloy of copper and zinc which contains 5 grams of zinc. If 15 grams of zinc are added to this alloy, a new alloy is obtained in which the copper content has been reduced by 30% from the original. Find the initial mass of the alloy

User Rich Fox
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1 Answer

3 votes

Answer:

Initial mass = 25 grams

Step-by-step explanation:


\left((x)/(x+20)\right)\:=\:\:\left((x)/(x+5)\:-.3\:\right)

x = 20 (mass of copper)


(20)/(20+5) = .8 = 80 percent


\\(20)/(20+15) = .5 = 50 percent

User Johel Alvarez
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