A game is played using one die. If the die is rolled and shows 1, the player wins $5. If the die shows any number other than 1, the player wins nothing. If there is a charge of $1 to play the game, what is the game's expected value?
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Let random variable "x" be a count of player gain.
X-values are: 4, -1
P(x=4) = 1/6; P(x= -1) = 5/6
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E(x) = (1/6)(4) + (5/6)(-1)
E(x) = [4-5]/6
E(x) = -1/6 = -17 cents
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Cheers,