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A metalworker has a metal alloy that is 30% copper and another alloy that is 55% copper. How many kilograms of each alloy should the metalworker combine to create 100 kg of a 50% copper alloy? The metal worker should use (blank) kilograms of the metal alloy that is 30% copper and (blank) kilograms of the metal alloy that is 55% copper. (show your work)​

User Garavani
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2 Answers

7 votes

Answer:

x=20kg

Explanation:

User Anarno
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3 votes

X+Y=100kg

X=100-Y

X*0.3+Y*0.55=100*0.5

(100-Y)*0.3+Y*0.55=50

30-0.3*Y+0.55*Y=50

0.25*Y=20

Y=80 kg

X=100-80

X=20 kg

The metal worker should use 20 kilograms of the metal alloy that is 30% copper and 80 kilograms of the metal alloy that is 55% copper.

User Timm
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