PROBABILITY

Introduction and Distribution of Probability

QUIZ ON CHAPTER FOUR: INTRODUCTION TO PROBABILITY



In the following multiple-choice questions, circle the correct answer.

1.The range of probability is

a.any value larger than zero b.any value between minus infinity to plus infinity

c.zero to one d.any value between -1 to 1

ANSWER:C

2. An experiment consists of three steps. There are four possible results on the first step, three possible results on the second step, and two possible results on the third step. The total number of experimental outcomes is

a.9 b.14 c.24 d. 36

ANSWER:C

3. A lottery is conducted using three urns. Each urn contains chips numbered from 0 to 9. One chip is selected at random from each urn. The total number of sample points in the sample space is

a.30 b.100 c.729 d.1,000

ANSWER:D

4.Of five letters (A, B, C, D, and E), two letters are to be selected at random. How many possible selections are there?

a.20 b.7 c.5! d.10

ANSWER:D

5. The “Top Three” at a racetrack consists of picking the correct order of the first three horses in a race. If there are 10 horses in a particular race, how many “Top Three” outcomes are there?

a.302,400 b.720 c.1,814,400 d.10

ANSWER:B

6. Of the last 100 customers entering a computer shop, 25 have purchased a computer. If the classical method for computing probability is used, the probability that the next customer will purchase a computer is

a.0.25 b. 0.50 c.1.00 d.0.75

ANSWER:B

7. An experiment consists of four outcomes with P(E1) = 0.2, P(E2) = 0.3, and P(E3) = 0.4. The probability of outcome E4 is

a.0.500 b.0.024 c.0.100 d.0.900

ANSWER:C

8.If P(A) = 0.38, P(B) = 0.83, and P(A ( B) = 0.57; then P(A ( B) =

a.1.21 b.0.64 c. 0.78 d. 1.78

ANSWER:B

9. If A and B are mutually exclusive events with P (A) = 0.3 and P (B) = 0.5, then

P (A ( B) =

a.0.30 b. 0.15 c. 0.00 d. 0.20

ANSWER:C

10.If A and B are mutually exclusive events with P (A) = 0.3 and P (B) = 0.5, then

P (A ( B) =

a. 0.00 b. 0.15 c. 0.8 d. 0.2

ANSWER:C

11.If P (A) = 0.80, P (B) = 0.65, and P (A ( B) = 0.78, then P (B(A) =

a. 0.6700 b. 0.8375 c. 0.9750 d. Not enough information is given to answer this question.

ANSWER:B

12.A six-sided die is tossed 3 times. The probability of observing three ones in a row is

a. 1/3 b.1/6 c.1/27 d.1/216

ANSWER:D

13.If a coin is tossed three times, the likelihood of obtaining three heads in a row is

a. zero b. 0.500 c 0.875 d. 0.125

ANSWER:D

14.A perfectly balanced coin is tossed 6 times and tails appears on all six tosses. Then, on the seventh trial

a. tails cannot appear b. heads has a larger chance of appearing than tails c. tails has a better chance of appearing than heads d. None of the other answers is correct.

ANSWER:D

15.Bayes' theorem is used to compute

a. the prior probabilities b. the union of events c. both the prior probabilities and the ...