First, lets see how many books we can keep in the shelves.
Each shelf = 28 books
Number of shelves - 3
Total books = 28 x 3 = 84
We have a total of 85 books, but 84 are in the shelves.
Thus, 85 - 84 = 1 book is in the stack.
Each shelf = 28 books
Number of shelves - 3
Total books = 28 x 3 = 84
We have a total of 85 books, but 84 are in the shelves.
Thus, 85 - 84 = 1 book is in the stack.
If there are a total of 85 books and 84 of them are on the shelves, then the remaining book must be in the stack.
Therefore, there is 1 book in the stack.
Total number of books on the shelves = 3 shelves * 28 books per shelf
= 84 books
To find the number of books in the stack, subtract the total number of books on the shelves from the total number of books:
Number of books in the stack = Total number of books - Total number of books on the shelves
= 85 books - 84 books
= 1 book
Therefore, there is 1 book in the stack.