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aalyn [17]
2 years ago
11

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
Mathematics
1 answer:
Ganezh [65]2 years ago
3 0

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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