Is a probability distribution defined if the only possible values of a random variable are 0, 1,2, 3, and P(0) = P(1) = P(2) = P(3) = 1/3?

Short Answer

Expert verified

No, the probability distribution is not defined if the only possible values of a random variable are 0, 1,2, 3, and P0=P1=P2=P3=13.

Step by step solution

01

Given information

The possible values of a random variable are 0,1,2,3.

The probabilities are given as,

P0=P1=P2=P3=13

.

02

Identify the requirements for a probability distribution

The requirements are as follows:

1)The variable x is anumerical random variable.

2)The sum of the probabilities is computed as,

Px=13+13+13+13=1.333

Therefore,the sum of the probabilities is not equal to 1 and is greater than 1.

3) Each value of P(x) is between 0 and 1.

Therefore, the probability distribution is not appropriately defined.

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