While the question is simple, with little details available, the answer is expected to be elaborate. Consider practicing with a peer, which is the most effective way to prepare for a real-life scenario.
Store Answering this problem just requires some simple algebra.
Or are you gunning for a broader target and wanting to demonstrate that your business is a thought leader in your industry? You are not being assessed on your mastery of business strategy.
Since the question is explicitly on marketing, I would assume it is not feasible to consider new products. Simple yes-or-no questions will probably elicit only single-word answers, forcing you to ask an awkward follow-up question. They are looking for evidence that candidates can communicate effectively with executives, and build durable, trusting business relationships with them.
Has there been any research completed to see how much customers are willing to pay for the product or similar ones?