Can anyone explain to me why does the working out says $6.9555 OR $7.5? I have got the value of $6.9555 but how do you get $7.5? And why do you use $7.5?

46. A stock is currently selling for $50. The stock price could go up by 10% or fall by 5% each month. The monthly interest rate is 1% (periodic rate). Calculate the price of an American put option on the stock with an exercise price of $55 and a maturity of two months. {Use the two-stage binomial method) L $5.10 B. $3.96 C. $4.73 D. None of the above p = l - (-SJIUO - (-5)) = 0.40 1-1) = 0.6 End of one month values: [(0)(0.4) + (2.75}(.6)]fl.01 = 1.6337 or zero and [(2.75){.4) + (9.875)(0.6)]7' 1.01 = $69555 or $7.5 if exercised; P = {0.40.6337} + (7.5)(0.6)]."1.01 = $5.10