1. Which of the following random variables is discrete?

a. Number of movies made by a director

b. Length of film used in a movie

c. Time needed to end a movie

d. Land area of a movie studio

2. If two dice are rolled, which of the following is NOT a possible outcome of the random variable X (total number of dots facing up)?

a. 2

b. 3

c. 10

d. 13

3. The mean for a probability is the same as the expected value of a discrete random variable of a probability distribution

a. True

b. False

c. Both

d. Neither

FOR NUMBERS 4-7, REFER TO THE PROBABILITY DISTRIBUTION BELOW.

A BIRTHING HOME RECORDED THE NUMBER OF LIVE BIRTHS THAT MATERIALIZE IN THEIR BIRTHING HOME IN THE PAST 2 YEARS

LIVE BIRTHS PER MONTH Y

(O 1 2 3 4 5)

PROBABILITY P(Y)

(O.11 O.15 0.23 0.25 0.13 0.13)

4. What is the probability that exactly 2 babies will be born in the home in any month?

a. 0.11

b. 0.15

c. 0.23

d. 0.25

5. What is the probability that at least 2 babies will be born in the home in any month?

a. 0.26

b. 0.51

c. 0.74

d. 0.89

6. What is the probability that at most 2 babies will be born in the home in any month?

a. O.26

b. 0.49

c. 0.74

d. 0.87

7. Tossing a die has the following probability distribution. What is the standard deviation of the number of spots that will appear when a die is tossed?

Number of spots Y

(1 2 3 4 5 6)

Proobability P(Y)

(1/6 1/6 1/6 1/6 1/6 1/6)

a. 0.167

b. 1.667

c. 1.7

d. 2.9

FOR NUMBER 8-10, REFER THE PROBABILITY DISTRIBUTION BELOW

Y 0 1 2 3 4 5

P(Y) 0.11 0.15 0.23 0.25 0.13 0.13

8. What is the mean of the probability distribution?

a. 2.23

b. 2.33

c. 2.43

d. 2.53

9. What is the variance of the probability distribution?

a. 2.25

b. 2.50

c. 2.75

d. 3.00

10. What is the standard deviation of the probability distribution?

a. 1.25

b. 1.50

c. 1.75

d. 2.00