You have three bowls: 7, 4 and 3 liters in capacity where only the 7-liter is full.

Pour the fewest times to have the bowls containing 2, 2 and 3 liters.

+2 votes

+1 vote

Fill the 4-liter from the 7-liter bowl. Fill the 3-liter from the 4-liter bowl. Now will have 3 liters left in the 7-liter,1 liter in the 4-liter and 3 in the 3-liter bowl. Now pour from the 3-liter to the 7-liter bowl, and then pour the 1 liter left in the 4-liter bowl to the 3-liter bowl. (Now it looks like 6,0,1)

Now fill the 4 from the 7 (Now it looks like 2,4,1)

Now fill the 3 from the 4 (Now it looks like 2,2,3)

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