Final answer:
Grace should bring 36 small wedges of cheese for lunch each day.
Step-by-step explanation:
To determine how much cheese Grace should bring for lunch each day, we need to divide the total amount of cheese by the number of days. Grace has three small rounds of cheddar cheese, and she wants to bring a small wedge of cheese for 12 days. So, the total amount of cheese she has is 3 small rounds x 12 days = 36 small wedges of cheese. Therefore, Grace should bring 36 small wedges of cheese for lunch each day.