STATS_Review_Lesson2

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

• 0, 1

• 0, 1, 2

• 1, 2, 3

• 0, 1, 2, 3

Suppose you tossed two coins. What are the sample spaces for the experiment?

• HH, TT

• HH, HT, TT

• HH, TH, TT

• HH, HT, TT, TH

What are the possible values of the random variable for the number of heads in a two coins?

• 0, 1

• 0, 1, 2

• 1, 2, 3

• 0, 1, 2, 3

What is the sum of the probabilities of all values of the random variable?

• ∑𝑃(𝑋))= 0

• ∑𝑃(𝑋)) = 1/10

• ∑𝑃(𝑋)) = 1

• ∑𝑃(𝑋)) = 10

If two balls are drawn in succession without replacement from an urn containing 5 red balls and 6 blue balls. If the value of the random variable X represents the number of blue balls, what is the probability of getting two blue balls?

• 1/8

• 1/4

• 1/3

• 1/2

What must be the value of the probability of each random variable?

• P(X) ≥ 0

• -1≤ P(X) ≤ 1

• 0≤ P(X) ≤ 1

• P(X) ≤ 1

Which of the following values is not the value of the probability of the random variable?

• 1.01

• 0.5

• 0.15

• 0.05

Which of the following values cannot serve as the values of a probability distribution?

• P(1) = 0.32, P(2) = 0.31, P(3)= 0.37

• P(1) = 9/14, P2) = 4/14, P(3)= 1/14

• P(1) = 0.08, P(2) = 0.12, P(3)= 1.03

• P(1) = 10/33, P(2) = 12/33, P(3)= 11/33

The following table shows the probability distribution of a discrete random variable X. Find the value of n.

• 0.15

• 0.25

• 0.45

• .6

If the values of the random variable X are 0,1,2 and 3 where X represents the number of heads in tossing a coin thrice, what is the probability that three heads will come up?

• 1/2

• 3/8

• 1/4

• 1/8