Answer: Alex paid $38.4 for the books.
Step-by-step explanation: Given that Alex bought six books priced at $8 each and he got a discount of 20% off the total cost.
We are to find the amount paid by Alex for the books.
We have
Price of 1 book = $8.
So, price of 6 books = $ (8 × 6) = $ 48.
After a discount of 20%, the cost of 6 books will be

Thus, Alex paid $38.4 for the books.