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 th

Question

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

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Nick 10 hours 2021-07-21T23:01:13+00:00 1 Answers 0 views 0

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    2021-07-21T23:03:11+00:00

    Answer:

    Initial mass = 25 grams

    Step-by-step explanation:

    \left(\frac{x}{x+20}\right)\:=\:\:\left(\frac{x}{x+5}\:-.3\:\right)

    x = 20 (mass of copper)

    \frac{20}{20+5}  = .8 = 80 percent

    \\\frac{20}{20+15}  = .5 = 50 percent  

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