To solve this problem you must apply the proccedure shown below:
1. Let's call
to the number of boxes of chocolate.
2. You have that he spends for month:

3. The problem says that Jeremy prices his chocolates at
the piece and offers a discount of
% on boxes of chocolate. Therefore, the price of a box is:

4. Therefore, you can write the following equation and solve for
:
The answer is:
boxes of chocolate.