Can anyone help me to solve part C of this question. I got stuck and really don't know how to find the expected value of the price.
Thank you
Do you know the definition of EV (expected value)? The best way to deal with this is to say that total price for the breakfast is $\displaystyle Z=X+Y$ where X is the cost of the sandwich and Y is the cost of the drink. Then you can calculate the EV of the whole meal as follows: $\displaystyle E(Z)=E(X+Y)=E(X)+E(Y)$
For Y you have:
$\displaystyle P(Y=0)=2/3$
$\displaystyle P(Y=2)=1/3$
$\displaystyle E(Y)=0*2/3 + 2 * 1/3 = 2/3$