probability distribution

A quantity resulting from an experiment by chance that can assume different values is called ____________.

• Random Sample

• Random Variable

• Random process

• Random experiment

Which of the following is NOT a true statement?

• Random variables can only have one value.

• The value of a random variable could be zero.

• The probability of all the value of a random variable could be zero.

• The sum of all the probabilities in a probability distribution is

  always equal to one.

If a coin is tossed, what are the possible values of the random variable for the number of heads?

• 0, 1

• 0, 1, 2

• 0, 1, 2, 3

• 1, 2, 3

Suppose you tossed two coins.

What is the sample space for the experiment above?

• {HH, TT}

• {HH, HT, TT}

• {HH, HT, TT}

• {HH, HT, TT, TH}

Suppose you tossed two coins.

Which of the following is NOT a possible value of the random variable for the number of heads?

• 1

• 2

• 3

• 4

In a local community, a couple was asked, “Are you satisfied with the work of the current president?” If the husband and the wife both said “yes”, the response is written as YY. If the husband said yes and the wife said “no”, the response is YN. If X is the number of “yes” responses, what are the possible values of the random variables?

• 0, 1, 2

• 1, 1, 2

• 1, 2, 3

• 2, 3, 4

Suppose two laptops are tested. Let D represent the defective laptop and N represent the non-defective laptop.What is the possible sample space for the experiment?

• {DD, NN}

• {DD, DN, NN}

• {DD, ND, NN}

• {DD, DN, NN, ND}

Which of the following values can serve as the probability distribution of a random variable X?

• 0, 2, 3

• 1, 1, 2

• 2, 3, 4

• 1, 2, 3

It is a random variable whose values are not countable but measurable.

(a)