Simple, just know that the first thing is for you to find d1 and d2.
d1 = [ln(So/X) + {r + (volatility^2)/2}*T] / volatility*T^1/2
then d2 = d1 - volatility*T^1/2.
Then the next step is for you to get the probability value, which will be done by rounding your values for d1 and d2 to 2 decimal numbers, say d1 = 0.52.
then you look up 0.5 under 0.02 to get the probability value, you do the same for d2.
Then you solve for the call and put price.
Call = So*Nd1 - Xe^(-r*T)*Nd2)
Put = Xe^(-r*T)*(1-Nd2) - So*(1-Nd1)
Note: Nd1 and Nd2 are the volatility values you looked up in the table.
Tadaaa… then we are done with the option pricing…
Just be weary that we can have a situation where instead of So which is the spot price, forward price may be used, that is using BSM in a forward pricing where a forward rate is used, in that case, you need to find the PV of the cash flow…e.t.c,
so, Call = e^(-r*T) * [(Ft*Ndi) - (X*Nd2)]
and Put = e^(-r*T) * [X*(1-Nd2) - Ft*(1-Ndi)]
This is because we are trying to discount the forward price back to its pv so as to compare it with the excersice price.
However, you need to be careful in calculating d1, as in this case, we are using the forward or future rate or price, and thus we will have to exclude the continuos compounded rate, because the forward rate or price is already compounded, thus our d1 formula becomes.
d1 = [ln(Ft/X) + ({volatility^2}/2)*T] / volatility*{T^(1/2)}
then d2 remains the same.
We can also apply it to interest rate option…
In fact, for me, the BSM is one of the easiest concept… cant wait for it to show up in the exam…
lol… Just take time to go through it, i am sure you will be fine with it.