1. **Problem Statement:** We have a cell phone plan costing 30 per month including 5GB of data. For each GB over 5, there is an additional charge of 7.50 per GB. After calculating the total, a 10% tax is applied. We want to find the equation for the total monthly cost $C$ when $x$ GBs are used and $x > 5$. 2. **Understanding the components:** - Base cost: 30 - Extra data used: $x - 5$ GB - Cost for extra data: $7.50 \times (x - 5)$ - Total before tax: $30 + 7.50(x - 5)$ - Tax: 10% of total before tax, so multiply by 1.10 3. **Formulating the equation:** The total cost including tax is: $$ C = (30 + 7.50(x - 5)) \times 1.10 $$ 4. **Matching with given options:** Option (E) is exactly: $$ C = (30 + 7.50(x - 5)) \cdot 1.10 $$ 5. **Conclusion:** The correct equation is option (E).