Discrete Probability - error with question?

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cyt91
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Homework Statement


On a long train journey, a statistician is invited by a gambler to play a dice game. The game uses 2 unbiased ordinary dice which the statistician is to throw. If the total score is 12, the statistician is paid 3 dollars by the gambler. However,if both or either dice show a '1', the statistician pays the gambler 2 dollars.

Let X= amount paid to the statistician by the gambler after the dice are thrown once.

Determine the probability that X=6,X=3 and X=-2.


I have one question...how do we determine the probability that X=6 since the question states that the statistician is paid 3 dollars by the gambler if the total score is 12 and X is the amount paid to the statistician after the dice are thrown once?

There's an error with the question isn't it? I need a second opinion on this. Thank you.
 
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Doesn't look like there's an error to me :D
 
How do you find the probability of X=6?
And the question states that X is the amount paid to the statistician in after the dice are thrown...once?
 
cyt91 said:

Homework Statement


On a long train journey, a statistician is invited by a gambler to play a dice game. The game uses 2 unbiased ordinary dice which the statistician is to throw. If the total score is 12, the statistician is paid 3 dollars by the gambler. However,if both or either dice show a '1', the statistician pays the gambler 2 dollars.
You are leaving out important information: What happens if the roll is, say 3, 3 so that neither condition is met? The probability that "both or either dice show a '1'" is 11/36 and the probability that "the total score is 12" is 1/36 so that there is a probability of 2/3 that neither condition is met.

Let X= amount paid to the statistician by the gambler after the dice are thrown once.

Determine the probability that X=6,X=3 and X=-2.


I have one question...how do we determine the probability that X=6 since the question states that the statistician is paid 3 dollars by the gambler if the total score is 12 and X is the amount paid to the statistician after the dice are thrown once?

There's an error with the question isn't it? I need a second opinion on this. Thank you.
Yes, you need to know what happens if neither condition is met. Surely the statistician isn't dumb enough to agree to pay the gambler $6 if neither condition is met!
 
HallsofIvy said:
You are leaving out important information: What happens if the roll is, say 3, 3 so that neither condition is met? The probability that "both or either dice show a '1'" is 11/36 and the probability that "the total score is 12" is 1/36 so that there is a probability of 2/3 that neither condition is met.


Yes, you need to know what happens if neither condition is met. Surely the statistician isn't dumb enough to agree to pay the gambler $6 if neither condition is met!

Ok. So there is an error with the question. Thanks a lot for your opinion.