White fat and fluffy,
May even look like a puppy.
Seems heavy but is light,
Floats about without a worry,
But if it turns dark you have to hurry!
Add me to myself and multiply by 4.
Divide me by 8 and you will have me once more.
What number am I?
It has the biggest wall and is also used when drinking tea.See answer
Select a pack of riddles and try to solve it in an interesting way.
This riddle appears in the following downloadable PDF files: