Consider a 5-month American put option on a nondividend-paying stock when the stock price is $50, the strike price is $50, the risk-free interest rate is 10% per annum, and the volatility is 40% per annum. Suppose that we divide the life of the option into five intervals of length 1 month (= 0.0833 years) for the purpose of constructing a binomial tree. What is the price of this American put option today?

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