Tony’s class needs more than $500 for the school dance. So far, they have raised $200. They plan to have a car wash, charging $8 a car, to raise more money. Tony solved the inequality 8x + 200 500, and determined that if they wash 37 cars, they will have enough money. Is he correct? Explain.

Answer:

No, Tony is not correct. When you solve the inequality 8x + 200 ≥ 500, you first subtract 200 from both sides to get 8x ≥ 300. Then, dividing by 8 gives x ≥ 37.5. Since the class must wash a whole number of cars, they need to wash at least 38 cars to meet their goal. 37 cars would only raise 37 * 8 + 200 = $496, which is less than $500.