Question
An alloy consists of 38% aluminum, 32% copper, and 30%
zinc. How much aluminum should be added to 60 kg of the alloy so that the new alloy contains 50% aluminum?Solution
ATQ,
Quantity of the alloy = 60 kg
Quantity of aluminum in 60 kg alloy = (0.38 × 60) = 22.8 kg
Quantity of copper in 60 kg alloy = (0.32 × 60) = 19.2 kg
Quantity of zinc in 60 kg alloy = (0.30 × 60) = 18 kg
Let the quantity of aluminum to be added be x kg.
According to the question,
Quantity of aluminum in the new alloy = (Quantity of copper + Quantity of zinc)
(22.8 + x) = (19.2 + 18)
Or, x = 37.2 - 22.8 = 14.4
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