To solve this problem, we need to calculate how many pizzas Carlos can make using the 4.5 pounds of flour he has, where each pizza requires $\frac{3}{4}$ pound of flour.

To do this, we divide the total flour Carlos has by the amount needed for one pizza:

$\frac{4.5}{\frac{3}{4}} = 4.5 \times \frac{4}{3}$

Now, let's compute the result:

$4.5 \times \frac{4}{3} = \frac{18}{3} = 6$

So, Carlos can make 6 pizzas.

It appears the correct answer should be "Carlos can make 6 pizzas," but the image highlights the incorrect option "Carlos can make 3 pizzas."

Would you like further clarification or details? Here are some related questions:

1. How do you simplify complex fractions like $\frac{4.5}{\frac{3}{4}}$?
2. How do you calculate the total number of items given a total and per-item amount?
3. What are the steps to convert a mixed number to an improper fraction?
4. How does multiplying by the reciprocal help in division problems?
5. How can you estimate the answer before calculating the exact result?

Tip: When dividing by a fraction, remember to multiply by its reciprocal.