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Question
An alloy of copper and zinc contains 45% copper and the rest is zinc. Find the weight of zinc in 20 kg of the alloy.
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Solution
Total weight of alloy = 20 kg
Weight copper = 20 × 45% = `20xx45/100` = 9 kg
Weight of zinc = (total weight of alloy – weight of copper)
= 20 – 9
= 11 kg
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