Pouring Water Puzzle Solution

Did you know the answer to this riddle?

The Solution

The Answer is: Fill the 5-liter bowl and pour water to the 3-liter bowl, which you empty afterwards. From the 5-liter bowl pour the 2 remaining liters to the 3-liter bowl. Refill the 5-liter bowl and fill in the 3-liter bowl (with 1 liter), so there stay the 4 required liters in the 5-liter bowl.