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TopNewestWhy not? First make them balance, you will have 12 pounds in one of the pans. Balance these 12 pounds you get 2 pans of 6 pounds. Keep one and the other balance again you will get 3 pounds. 6 pounds+3 pounds=9 pounds. Or did I misunderstood (a restriction how many times to use the balance etc.) – Yong See Foo · 4 years, 6 months ago

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Divide the into 2 and put it in each pan until they become equal. So you have 12 pounds on one pan. Then divide that 12 pounds of nails into 2 and put it in each pan until they become equal. So you have 6 pounds. Then divide that 6 pounds of nails into 2 two put it in each pan until they become equal. So you have 3 pounds. Combine that 6 pounds and 3 pounds. Now you will get 9 pounds. – Shriram S B · 4 years, 6 months ago

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