1. **State the problem:** Martina buys $p$ pounds of chocolate, each pound costing 8 dollars. We want to write an equation for the total cost $c$. 2. **Identify variables:** Let $p$ be the number of pounds bought. Let $c$ be the total cost. 3. **Write the formula:** Total cost is price per pound times number of pounds: $$c = 8 \times p$$ 4. **Explain:** Since each pound costs 8 dollars, multiplying 8 by the number of pounds $p$ gives the total cost $c$. 5. **Final equation:** $$c = 8p$$ This equation represents the total cost Martina pays for $p$ pounds of chocolate.