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=<<6-2=4>>4 liters that can be added.
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