Simple Chooser Options
The price of a simple chooser option is given by : 
where 

where 
S = The spot of the underlying asset b = The cost of carry r = The risk free rate X = The strike price = Volatility of underlying asset's price t_{1} = Time to when the holder must choose call or put T_{2} = Time to maturity N = The cumulative normal distribution function 

See Also 
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