Question 478412
Determine whether each of the distributions given below represents a probability distribution. Justify your answer. 
(A) 

x 1 2 3 4
P(x) 1/4 5/12 1/3 1/6 
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No: P(x)'s add to more than 1.
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(B) 

x 3 6 8
P(x) 0.1 3/5 0.3
Yes
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(C) 

x 20 30 40 50
P(x) 0.2 -0.2 0.7 0.3
No: P(x) cannot be negative

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Cheers,
Stan H.
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