Final answer:
To find the number of children's books Cindy bought, divide the amount she spent on children's books by the price of each book. The correct answer is C. 5.
Step-by-step explanation:
To find the number of children's books Cindy bought, we need to determine the total amount she spent on children's books and divide it by the price of each book.
Let's first calculate the amount Cindy spent on paperback books. Since she bought 2 paperback books for $1.75, the cost of each paperback book is $1.75/2 = $0.875.
Now, let's calculate the amount she spent on children's books. Since she spent a total of $5.75 and the cost of each children's book is $0.75 (including tax), the amount spent on children's books is $5.75 - $1.75 = $4.
Finally, we can determine the number of children's books by dividing the amount spent on children's books by the price of each book. $4 / $0.75 = 5.33. Since we can't have a fraction of a book, Cindy must have bought 5 children's books.
Therefore, the correct answer is C. 5.