Stats Ch 4 multiple choice

29. A representative of the Environmental Protection Agency wants to select samples from 5 landfills. The Director has 10 landfills from which to collect samples. How many different samples are possible? a. 7,500 b. 27,000 c. 36,000 d. 30,240

d. 30,240

12. Three applications for admission to a local university are checked, and it is determined whether each applicant is male or female. The number of sample points in this experiment is a. 2 b. 4 c. 6 d. 8

d. 8

14. Each customer entering a department store will either buy or not buy some merchandise. An experiment consists of following 3 customers and determining whether or not they purchase any merchandise. The number of sample points in this experiment is a. 2 b. 4 c. 6 d. 8

d. 8

13. Assume your favorite football team has 2 games left to finish the season. The outcome of each game can be win, lose or tie. The number of possible outcomes is a. 2 b. 4 c. 6 d. 9

d. 9

1. If two events are independent, then a. they must be mutually exclusive b. the sum of their probabilities must be equal to one c. their intersection must be zero d. None of these alternatives is correct.

d. None of these alternatives is correct.

31. Independent events A and B would be consistent with which of the following statements:. a. P (A) = .5, P (B) = .4, P (A ∩ B) = .3 b. P (A) = .4, P (B) = .3, P (A ∩ B) = .5 c. P (A) = .3, P (B) = .5, P (A ∩ B) = .4 d. P (A) = .4, P (B) = .5, P (A ∩ B) = .2

d. P (A) = .4, P (B) = .5, P (A ∩ B) = .2

15. When the assumption of equally likely outcomes is used to assign probability values, the method used to assign probabilities is referred to as the a. relative frequency method b. subjective method c. probability method d. classical method

d. classical method

2. Bayes' theorem is used to compute a. the prior probabilities b. the union of events c. intersection of events d. the posterior probabilities

d. the posterior probabilities

8. The National Centre for Health Statistics reported that of every 883 deaths in recent years, 24 resulted from an automobile accident, 182 from cancer and 333 from heart disease. Using the relative frequency approach, what is the probability that a particular death is due to an automobile accident? A) 24/883 or 0.027 B) 539/883 or 0.610 C) 24/333 or 0.072 D) 182/883 or 0.206 E) None of the choices are correct

A) 24/883 or 0.027

38.Given the information below, find P(S ∩ W). Cell Phone Service Provider County Sprint (S) AT&T (A) Verizon (V) Row Total Macomb (M) 17 25 8 50 Oakland (O) 19 38 13 70 Wayne (W) 24 37 19 80 Col Total 60 100 40 200 a. .12 b. .30 c. .40 d. .58

a. .12

36. Given the information below, find P(V). Cell Phone Service Provider County Sprint (S) AT&T (A) Verizon (V) Row Total Macomb (M) 17 25 8 50 Oakland (O) 19 38 13 70 Wayne (W) 24 37 19 80 Col Total 60 100 40 200 a. .20 b. .40 c. .50 d. .80

a. .20

39. If A and B are independent events with P(A) = 0.65 and P(A ∩ B) = 0.26, then, P(B) = a. 0.400 b. 0.169 c. 0.390 d. 0.650

a. 0.400

30. A national pollster has developed 15 questions designed to rate the performance of the Prime Minister of Canada. The pollster will select 10 of these questions. How many different arrangements are there for the order of the 10 selected questions? a. 10,897,286,400 b. 27,897,286,100 c. 36,997,286,400 d. 6,697,386,100

a. 10,897,286,400

28. An overnight express company must include five new cities on its routes. How many different routes possible, assuming that it does not matter in which order the cities are included in the routing? a. 120 b. 75 c. 136 d. 125

a. 120

22. In an experiment, events A and B are mutually exclusive. If P(A) = 0.6, then the probability of B a. cannot be larger than 0.4 b. can be any value greater than 0.6 c. can be any value between 0 to 1 d. cannot be determined with the information given

a. cannot be larger than 0.4

40. The counting rule that is used for counting the number of experimental outcomes when n objects are selected from a set of N objects where order of selection is important is called a. permutation b. combination c. multiple step experiment d. None of these alternatives is correct.

a. permutation

16. When the results of experimentation or historical data are used to assign probability values, the method used to assign probabilities is referred to as the a. relative frequency method b. subjective method c. classical method d. posterior method

a. relative frequency method

37. Given the information below, find P(V |W). Cell Phone Service Provider County Sprint (S) AT&T (A) Verizon (V) Row Total Macomb (M) 17 25 8 50 Oakland (O) 19 38 13 70 Wayne (W) 24 37 19 80 Col Total 60 100 40 200 a. .2000 b. .2375 c. .0950 d. .4000

b. .2375

5. If P(A) = 0.4, P(B | A) = 0.35, P(A ∪ B) = 0.69, then P(B) = a. 0.14 b. 0.43 c. 0.75 d. 0.59

b. 0.43

11. An experiment consists of selecting a student body president and vice president. All undergraduate students (freshmen through seniors) are eligible for these offices. How many sample points (possible outcomes as to the classifications) exist? a. 4 b. 16 c. 8 d. 32

b. 16

27. Assume your favorite football team has 3 games left to finish the season. The outcome of each game can be win, lose, or tie. How many possible outcomes exist? a. 7 b. 27 c. 36 d. 64

b. 27

21. A method of assigning probabilities which assumes that the experimental outcomes are equally likely is referred to as the a. objective method b. classical method c. subjective method d. experimental method

b. classical method

4. The counting rule that is used for counting the number of experimental outcomes when n objects are selected from a set of N objects where order of selection is not important is called a. permutation b. combination c. multiple step experiment d. None of these alternatives is correct.

b. combination

33. Two events are complementary (i.e., they are complements) if a. the sum of their probabilities equals one. b. they are disjoint and their probabilities sum to one. c. the joint probability of the two events equals one. d. they are independent events with equal probabilities.

b. they are disjoint and their probabilities sum to one.

35. The manager of PayALot Drug Store knows that 30% of the customers entering the store buy prescription drugs, 60% buy over-the-counter drugs, and 18% buy both types of drugs. What is the probability that a randomly selected customer will buy either one or the other of these two types of drugs? a. .50 b. .90 c. .72 d. .30

c. .72

25. If P(A) = 0.48, P(A ∪ B) = 0.82, and P(B) = 0.54, then P(A ∩ B) = a. 0.3936 b. 0.3400 c. 0.2000 d. 1.0200

c. 0.2000

7. Given that event E has a probability of 0.31, the probability of the complement of event E a. cannot be determined with the above information b. can have any value between zero and one c. 0.69 d. is 0.31

c. 0.69

18. 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

c. 0.8

3. From a group of six people, two individuals are to be selected at random. How many possible selections are there? a. 12 b. 36 c. 15 d. 8

c. 15

20. Events A and B are mutually exclusive. Which of the following statements is also true? a. A and B are also independent. b. P(A ∪ B) = P(A)P(B) c. P(A ∪ B) = P(A) + P(B) d. P(A ∩ B) = P(A) + P(B)

c. P(A ∪ B) = P(A) + P(B)

17. The union of events A and B is the event containing a. all the sample points belonging to B or A b. all the sample points belonging to A or B c. all the sample points belonging to A or B or both d. all the sample points belonging to A or B, but not both

c. all the sample points belonging to A or B or both

23. The set of all possible sample points (experimental outcomes) is called a. a sample b. an event c. the sample space d. a population

c. the sample space

32. If P(AB) = 0.40 and P(B) = 0.30, find P(A ∩ B). a. .171 b. .525 c. .571 d. .120

d. .120

24. If P(A) = 0.45, P(B) = 0.55, and P(A ∪ B) = 0.78, then P(A B) = a. zero b. 0.45 c. 0.22 d. 0.40

d. 0.40

19. Events A and B are mutually exclusive with P(A) = 0.3 and P(B) = 0.2. Then, P(Bc) = a. 0.00 b. 0.06 c. 0.7 d. 0.8

d. 0.8

34. If each of two independent file servers has a reliability of 93% and either alone can run the web site, then the overall web site availability is a. 0.8649 b. 0.9300 c. 0.9522 d. 0.9951

d. 0.9951

6. 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

d. 10

26. Each customer entering a department store will either buy or not buy some merchandise. An experiment consists of following 4 customers and determining whether or not they purchase any merchandise. How many sample points exist in the above experiment? (Note that each customer is either a purchaser or non-purchaser.) a. 2 b. 4 c. 12 d. 16

d. 16

9. Which approach to probability is exemplified by the following formula? A) Classical approach B) Empirical approach C) Subjective approach D) None of the choices are correct

B) Empirical approach

10. A board of directors consists of eight men and four women. A four-member search committee is to be chosen at random to recommend a new company president. What is the probability that all four members of the search committee will be women? A) 1/120 or 0.00083 B) 1/16 or 0.0625 C) 1/8 or 0.125 D) 1/495 or 0.002 E) None of the choices are correct

D) 1/495 or 0.002