An alloy contains zinc, copper and tin in the ratio 3 : 2 : 2 and another contains copper, tin and lead in the ratio 2 : 3 : 5. If equal weights of both alloys are melted together to form a third alloy, then the weight of lead per kg in new alloy will be:
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Correct answer: C
Explanation
Given:
The first alloy contains zinc : copper : tin = 3 : 2 : 2
The second alloy contains copper : tin : lead = 2 : 3 : 5
The weights of both alloys are the same.
Assume the weights of both alloys = 1 kg + 1 kg
First alloy
Total parts = 3 + 2 + 2 = 7
Lead = 0
Second alloy
Total parts = 2 + 3 + 5 = 10
Part of lead = 5/10 = 0.5 kg
Now the total alloy = 2 kg
Total lead = 0.5 kg
Lead per kg = 0.5 / 2 = 0.25 kg