To find the unit rate of orders per day, you divide the total number of orders by the total number of days.
Here, you have 25 orders in 5 days:
\[ \text{Unit rate} = \frac{\text{Total Orders}}{\text{Total Days}} = \frac{25 \text{ orders}}{5 \text{ days}} = 5 \text{ orders per day} \]
So, the unit rate is 5 orders per day.