Give the step-by-step reasoning process and then the final answer. Hamza has several empty buckets of different sizes, holding either 3, 5, or 6 liters. She fills the 5-liter bucket and pours as much as she can into the 3-liter bucket. Then, she pours the remainder into the 6-liter bucket. How much more water, in liters, can she put into the 6-liter bucket, without overflowing?
Pouring the 5 - liter bucket into the 3 - liter bucket leaves 5 - 3 = 2 liters, which go into the 6 - liter bucket. Then there are 6 - 2 = 4 liters that can be added.
The final answer: 4.