Question 402732
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Because 0.20 + 0.20 + 0.23 + 0.54 + 0.29 = 1.46

and to be a discrete probability distribution function all the
probabilities must be positive, less than 1 and their sum must
be 1.  Their sume here is 1.46, not 1.  That is why it is not a
discrete probability distribution function.

[Note: it is NOT because the x-values are negative.  x-values can
be any numbers, positive negative or zero.]

Edwin</pre>