Question

An alloy contains copper and zinc in the ratio 7:3. If it contains 12.6g of copper, how much does this alloy weigh?

Answer 1

copper : zinc
7 : 3
12.6g : ?
7x = 12.6
x = 12.6/7
= 1.8

3x = ?
3(1.8)=5.4g
copper = 7x = 12.6g
zinc = 3x = 5 4g

weigh of the alloy =12.6+5.4
=18 g

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