Answer:
412.8
Step-by-step explanation:
The price of one set of sheet is

Here Carla wants to buy 8 sets of sheets; however, there is a 2x1 discount, this means that the price she pays will be the price of only 4 sets of sheets, so:

However, we are also told that there is an additional 20% discount.
The amount of the discount is:

So the discounted price will be:

So, Carla will pay 412.8 soles.