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There are $12$ plates of biscuits with $3$ identical biscuits on each plate.
(They are named simply to help identify them by a letter!)
Can you rearrange the biscuits on the plates so that
For example, if you have one plate of 'A, D and F' then you cannot have another with both 'A and D' or 'A and F' or 'D and F'.
How can you put five cereal packets together to make different shapes if you must put them face-to-face?