Let x be the amount of the metal alloy that is 25% copper.
Then the amount of the metal alloy that is 75% copper is 90kg - x.
The amount of copper in the 25% copper alloy is 0.25x.
The amount of copper in the 75% copper alloy is 0.75(90kg - x).
The total amount of copper in the final alloy is 0.55(90kg).
0.25x + 0.75(90kg - x) = 0.55(90kg)
0.25x + 67.5kg - 0.75x = 49.5kg
0.5x = 67.5kg - 49.5kg
0.5x = 18kg
x = 36kg
The metalworker should use 36 kilograms of the metal alloy that is 25% copper and 90kg - 36kg = 54 kilograms of the metal alloy that is 75% copper. Answer: \boxed{36, 54}.
A metalworker has a metal alloy that is 25% copper and another alloy that is 75% copper. How many kilograms of each alloy should the metalworker combine to create 90kg of a 55% copper alloy?
the metalworker should use ___ kilograms of the metal that is 25% copper and ___ kilograms of the metal alloy that is 75% copper
1 answer
1 answer