Question

On your next turn in a board game there is a 60% chance that you will move ahead 4 spaces and a 40% chance that you will move back 2 spaces. What is the expected value for the number of spaces moved?
A. 1.2 spaces forward
B. 1.6 spaces forward
C. 2 spaces forward
D. 3.4 spaces forward

Answer 1

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.