There are 5,040 different ways in which she can order the books.
<h3>
In how many ways can she put the books on the shelf?</h3>
We know that Donna has 9 books, but 2 of these books already have fixed positions (the first one and the last one).
So we only need to order the remaining 7 books in 7 positions.
- On the first position, we have 7 options (7 books to put there).
- On the second position, we have 6 options (because one book is already in the first position).
- On the third position, we have 5 options.
And so on for the remaining positions.
The total number of different combinations in which she can order the books is given by the product between the numbers of options above, so we will get:
C = 7*6*5*4*3*2*1 = 5,040
If you want to learn more about combinations:
brainly.com/question/251701
#SPJ1
