Question 239964
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Presuming that they are 7 different books, there are 7 ways to pick the first book.  Then for each of those ways, there are 6 ways to pick the second book.  Hence there are 42 ways to arrange the first two books.  Then for each of those 42 ways there are 5 ways to select the third book, so 42 times 5...continue this process until you have selected all the books.


Mathematical shorthand: *[tex \LARGE 7!]


John
*[tex \LARGE e^{i\pi} + 1 = 0]
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