Cesar took his mom out to lunch. They shared a pizza, which cost \( \$ 9.78 \), and they shared a salad, which cost \( \$ 4.29 \). Cesar's mom had coffee, which cost \( \$ 1.10 \). How much did Cesar spend for lunch?

First, let's add up the costs of the pizza, salad, and coffee. The pizza costs \( \$ 9.78 \), the salad costs \( \$ 4.29 \), and the coffee costs \( \$ 1.10 \). So, the total cost is: \[ \$ 9.78 + \$ 4.29 + \$ 1.10 = \$ 15.17 \] Cesar spent a total of \( \$ 15.17 \) for lunch. Now, if you're looking to avoid any confusion with addition, consider breaking the numbers down. Round \( 9.78 \) to \( 10.00 \) to make quick mental math easier, then adjust back to find the exact total. Additionally, always double-check your calculations to avoid small mistakes!