This question is a classic Fermi problem, designed to assess your problem-solving and estimation skills rather than your knowledge of specific sales figures. To approach it, I would first ask clarifying questions, such as the definition of a "Hershey's chocolate bar" (e.g., does it include all sizes and product lines?) and the timeframe for "last year." Then, I'd break down the problem into manageable components: estimating the US population, the percentage of the population that consumes chocolate, the average consumption rate per person, and the proportion of that consumption that is Hershey's. By making reasonable assumptions for each variable and performing back-of-the-envelope calculations, I can arrive at a plausible estimate. The goal is to demonstrate a structured thought process and logical reasoning.
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