Amanda is buying snacks for a party she's throwing at her house. She wants to make sure there is enough food for everyone. She wants to buy some bags of pretzels. Each bag contains 7 servings, She is planning to have 30 guests at her party. To determine how many bags she needs to buy, she sets up an inequality and solves it. She determines that she needs to buy at least 4 bags of pretzels to ensure that anyone has at least one serving.

Is she correct? Explain the reasoning.