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Years ago there was a poor shop keeper who had a small amount of money enough to buy only FOUR weight bars for his an old weigh scale. Now the problem is he can buy only FOUR weight bars and he has to deal with customers who buy 1 to 40 Kilograms goods from his shop so What weight of Weighing scale bars shop keeper should buy?
- Shop Kipper can't weight goods for one customer more than once like: If the customer wants to buy 20 KG apple Kipper can't weight 10KG + 10KG twice.
- The total weight of all 4 weight bar should be 40 neither more nor less.
Source: Grandma :)