Answer:
720 different ways.
Explanation:
Permutation has to do with arrangement. For example, in order to arrange 'n' objects in any order, this can only be done in n! ways since there is no condition or restriction on how to arrange the objects.
n! = n(n-1)(n-2)... (n-r)!
If there are 3 statistics books, 2 math books, and 1 computer science book on your bookshelf, the total number of books altogether is 3 + 2 + 1 = 6 books.
The number of ways that 6 books can be arranged in any order is 6!.
6! = 6(6-1)(6-2)(6-3)(6-4)(6-5)
6! = 6*5*4*3*2*1
6! = 120*6
6!= 720 different ways.
Hence, the books on your shelf can be arranged in 720 different ways.