Question

15 pointsThe Witches' Duel is a game of chance. On each turn, there are four possible outcomes:You earn 1 point with probability.2, and you lose 1 point with probability .3.You earn 5 points with probability .35, and you lose 5 points with probability .15.On average, how many points do you eam on each turn?2.1 ptsE O O O OO0.9 pts3.5 pts3.2 pts1.4 pts

Answer 1

SOLUTION

We will apply the formula for expected value which is

$\Sigma P\text{ = }\Sigma X_{n\text{ }}P_n$

That is Expected value is the summation of the (points x probabilities).

For win, we add, for lose, we subtract. This becomes

$\begin{gathered} \Sigma P\text{ = 1(0.2) - 1(0.3) + 5(0.35) -5(0.15)} \\ \Sigma P\text{ = 0.2 - 0.3 + 1.75 - 0.75} \\ \Sigma P\text{ = 0.9 } \end{gathered}$

Therefore, the correct answer is 0.9 points