Respuesta :
Answer:
There are 256 ways of arranging the 4 books as a pile on the desk
Step-by-step explanation:
Since you take 4 random books from the 20 total books found, we can assume those 4 books are the ones that need to be taken back and do NOT get swapped for other books that you found. That being the case, we need to find how many possible ways there are to arrange those 4 books as a pile on top of the desk. This can be done by raising the amount of books on the pile to its same power like shown below
[tex]4^{4} = 256[/tex]
So there are 256 ways of arranging the 4 books as a pile on the desk.
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