The current price of a non-dividend-paying stock is $69.65 and you expect the stock price to either go up by a factor of 1.224 or down by a factor of 0.837 each period for 2 periods over the next 0.8 years. Each period is 0.4 years long.
A European put option on the stock expires in 0.8 years. Its strike price is $70. The risk-free rate is 3% (annual, continuously compounded).
What is the current value of the option?