Question
Two alloys are combined to create a new alloy. The first
alloy contains 20% copper, and the second alloy contains 40% copper. If the resulting alloy has 30% copper and weighs 60 kg, what is the weight of the first alloy used?Solution
Using alligation method the ratio of alloys = (40%-30%): (30%-20%) = 1: 1 Total weight = 60 kg the weight of the first alloy used = 60/2 = 30 kg
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