To determine how many pounds of books will be in each box, we need to divide the total weight of the books, which is 85 pounds, by the number of boxes, which is 4.
We can perform the division as follows:
\[ \frac{85}{4} \]
Now, we can perform the division:
- Divide 85 by 4.
- 4 goes into 8 two times (since \(4 \times 2 = 8\)).
- Subtract 8 from 8, which gives us 0, and bring down the next digit (5).
- Now, we have 05.
- 4 goes into 5 one time (since \(4 \times 1 = 4\)).
- Subtract 4 from 5, which gives us 1.
The result of the division is:
\[ 85 \div 4 = 21\ R1 \]
Thus, as a mixed number, this can be expressed as:
\[ 21 \frac{1}{4} \]
Therefore, the weight of books in each box is
\[ \boxed{21 \frac{1}{4}} \text{ pounds.} \]