Respuesta :
Answer:
The expected value of X is $0.0833.
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
For each dice, there are 6 possible outcomes(values from 1 to 6). So for 2 dices, there are [tex]6^2 = 36[/tex] desired outcomes.
Desired outcomes:
Sum 5: (1,4), (2,3), (3,2), (4,1).
Sum 6: (1,5),(2,4),(3,3),(4,2),(5,1)
Sum of 9: (3,6), (4,5), (5,4), (6,3)
Sum of 10: (4,6), (5,5), (6,4)
Sum of 12: (6,6)
Probabilities:
5 + 3 = 8 outcomes in which the sum is 6 or 10, that is, 8/36 probability of winning $4.
4 + 4 + 1 = 9 outcomes in which the 5, 9, or 12, that is, 9/36 probability of winning $1.
36 - (8 + 9) = 36 - 17 = 19 remaining outcomes, that is, 19/36 probability of losing $2.
What is the expected value of X?
Multiplication of each outcome by its probability. So
[tex]E(X) = \frac{8}{36}*4 + \frac{9}{36}*1 - \frac{19}{36}*2 = \frac{8*4 + 9*1 - 19*2}{36} = \frac{32 + 9 - 38}{36} = \frac{3}{36} = 0.0833[/tex]
The expected value of X is $0.0833.
