Estimate the number of restaurants in San Francisco.

Focus on breaking down the problem into manageable components. Start by defining the geographical area of San Francisco and consider the population size. Think about the average number of people per household and their dining habits, such as how often they eat out. Use these figures to estimate the number of potential diners, and then determine the average number of restaurants needed to serve that population. Consider different types of restaurants (fast food, casual dining, fine dining) and how they might influence your estimate. Be prepared to explain your assumptions and the rationale behind your calculations.