The expectation value is simply obtained by multiplying the probability of each outcome by each possible value. These are then summed for each outcome to obtain the expectation value. In the board game, if there is a 60% chance that you will move 4 spaces forward (+4) and a 40% chance that you will move back 2 spaces then expected value for number of spaces is (0.6 x 4) + (0.4 x -2) = 2.4 - 0.8 = 1.6 spaces.
