To find the unit rate of cupcakes per box, divide the total number of cupcakes by the number of boxes:
\[ \text{Unit Rate} = \frac{\text{Total Cupcakes}}{\text{Total Boxes}} = \frac{49 \text{ cupcakes}}{7 \text{ boxes}} = 7 \text{ cupcakes per box} \]
So, there are 7 cupcakes per box.