Tomorrow, Mrs. Wendel's class will be using toothpicks for a science project. Each student must use at least 9 toothpicks for the project.  Mrs. Wendel knows that there is already a bag of 50 toothpicks in the class storage room. She plans to buy x additional toothpicks this afternoon to make sure her class will have enough. If her class has 30 students, which number sentence represents this situation?

Respuesta :

1)  Each student must use at least 9 toothpicks for the project and her class has 30 students, so

at least 9*30 toothpicks are needed.

2)  Mrs. Wendel has already 50 toothpicks,

so she needs to buy at least (9*30 - 50).

x ≥ 9*30 - 50