SOLUTION: 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 1/12 1/3

Algebra ->  Probability-and-statistics -> SOLUTION: 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 1/12 1/3       Log On


   



Question 552287: 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
1/12
1/3
1/6



(B)
x
3
6
8

P(x)
0.2
2/5
0.3



(C)
x
20
35
40
50

P(x)
0.3
-0.1
0.5
0.3





Found 2 solutions by richard1234, stanbon:
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
A: no, probabilities don't add to 1

B: no, same reasons as A

C: no, can't have negative probability

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
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 = 3/12
1/12 = 1/12
1/3 = 4/12
1/6 = 2/12
----
Not a p.d.: probs do not sum to 1.
===========================================
(B)
x
3
6
8
P(x)
0.2 = 0.2
2/5 = 0.4
0.3 = 0.333
---
No because probs do not sum to 1.
======================================
(C)
x
20
35
40
50
P(x)
0.3
-0.1
0.5
0.3
--
No because a probability cannot be negative
===============
Cheers,
Stan H.
===============