Answer:
26
Explanation:
The empty space in the barrel is ...
25.5 L -5.2 L = 20.3 L
Each time Kelly uses her bucket, she puts up to 0.8 L more water into the barrel. She needs to do that ...
20.3/0.8 = 25.375
more times.
Kelly needs to use her bucket 26 times to finish filling the barrel.
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We don't know how to build a bear with a bucket of any size.