Step 1: Understanding the Concept:
This question asks about the financial situation of the banker at the end of the fifteen-year period in Anton Chekhov's story, 'The Bet'.
Step 2: Detailed Explanation:
At the beginning of the story, the banker is extremely wealthy, arrogant, and confident. He has millions to spare.
However, during the fifteen years that the lawyer is imprisoned, the banker's fortunes take a downturn. He makes risky investments, gambles on the stock exchange, and his wealth declines significantly.
By the time the bet is nearing its end, the banker realizes that paying the two million rubles to the lawyer would lead to his complete financial ruin. He is heavily in debt and no longer the affluent man he once was.
Step 3: Final Answer:
After fifteen years, the rich banker was in debt.