Question 558874
Determine whether each of the distributions given below represents a probability distribution. Justify your answer. 
(A) 
x
1
2
3
4

P(x)
1/8 = 2/16
3/16
1/4 = 4/16
7/16
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Sum = 16/16 so it is a probability distribution
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(B) 
x
3
6
8

P(x)
0.2 = 2/10 = 16/80
3/8 = 30/80
0.4 = 4/10 = 32/80
Does not add up to 1 so is not a probabity distribution


(C) 
x
20
35
40
50

P(x)
0.2
0.4
-0.3
0.7
Has a negative value in it so is not a p.d.
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Cheers,
Stan H.
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