In: Statistics and Probability
Probability Distribution |
|
X |
P (X) |
b)How much should the casino charge for this game if they want to make a profit in the long run? Show the calculations that support your decision
c)What is the standard error, σX, for this gamble
Distribution of X |
||
X |
P (X = k) |
P (X ≤ k) |
0 |
||
1 |
0.4219 |
|
2 |
||
3 |
0.0469 |
|
4 |
0.0039 |
We would be looking at the first question all parts here:
a) For 2 four sided dice, the total number of combinations is
computed as:
= 4*4 = 16
Therefore the probability distribution of the sum of the two numbers is obtained here as:
P(Sum = 2) = P(11) = 1/16
P(Sum = 3) = P(12, 21) = 2/16
P(Sum = 4) = P(13, 31, 22) = 3/16
P(Sum = 5) = P(14,23,42,41) = 4/16
P(Sum = 6) = P(24,42,33) = 3/16
P(Sum = 7) = P(34,43) = 2/16
P(Sum = 8) = 1/16
Using this, the PDF for the gamble is obtained here as:
P(X = 25) = P(3 <= Sum <= 5) = ( 2 + 3 + 4)/16 =
0.5625
P(X = 100) = P(Sum >= 6) = (3 + 2 + 1)/16 = 0.375
P(X = 0) = 1 - 0.5625 - 0.375 = 0.0625
Therefore the PDF for gamble here is given here
as:
P(X = 0) = 0.0625,
P(X = 25) = 0.5625,
P(X = 100) = 0.375
b) To be profitable in long run, the casino should charge more than the expected value of the gamble to the player here. This is computed as:
Therefore the casino should charge more than 51.5625 here to be profitable in long run.
c) The second moment of X is first computed here as:
The standard deviation of X now is computed here as:
Therefore 37.9851 is the required standard deviation here.