Deck 5: Probability

Question 1

Grandma's predicting rain based on how much her arthritis is acting up is an example of the classical view of probability.

Answer 1

False

Question 2

For any event A,the probability of A is always 0 ≤ P(A)≤ 1.

Answer 2

True

Question 3

If events A and B are mutually exclusive,the joint probability of the events is zero.

Answer 3

True

Question 4

Events A and B are mutually exclusive if P(A ∩ B)= 0.

Question 5

The empirical view of probability is based on relative frequencies.

Question 6

The odds of an event can be calculated by dividing the event's probability by the probability of its complement.

Question 7

A sample space is the set of all possible outcomes in an experiment.

Question 8

The probability of A and its complement (A´)will always sum to one.

Question 9

If events A and B are dependent,it can be concluded that one event causes the other.

Question 10

If A and B are mutually exclusive events,then P(A ∩ B)= P(A)+ P(B).

Question 11

Probability is the measure of the relative likelihood that an event will occur.

Question 12

The probability of the union of two events P(A or B)can exceed one.

Question 13

If events A and B are mutually exclusive,then P(A)+ P(B)= 0.

Question 14

The sum of all the probabilities of simple events in a sample space equals one.

Question 15

Two events A and B are independent if P(A | B)is the same as P(A).

Question 16

Independent events are mutually exclusive.

Question 17

When the outcome of a random experiment is a continuous measurement,the sample space is described by a rule instead of listing the possible simple events.

Question 18

The general law of addition for probabilities says P(A or B)= P(A)+ P(B)- P(A ∩ B)

Question 19

The sum of the probabilities of all compound events in a sample space equals one.

Question 20

If A and B are independent events,then P(A or B)= P(A)P(B).

Question 21

If P(A)= 0.50,P(B)= 0.30,and P(A ∩ B)= 0.15,then A and B are independent events.

Question 22

When two events A and B are independent,the probability of their intersection can be found by multiplying their probabilities.

Question 23

The sum of the probabilities of two mutually exclusive events is one.

Question 24

The value of 7! is 5040.

Question 25

Independent events A and B would be consistent with which of the following statements:

A) P(A)= .3,P(B)= .5,P(A ∩ B)= .4.
B) P(A)= .4,P(B)= .5,P(A ∩ B)= .2.
C) P(A)= .5,P(B)= .4,P(A ∩ B)= .3.
D) P(A)= .4,P(B)= .3,P(A ∩ B)= .5.

Question 26

The probability of events A or B occurring can be found by summing their probabilities.

Question 27

Two events are mutually exclusive when they contain no outcomes in common.

Question 28

A contingency table is a cross-tabulation of frequencies for two categorical variables.

Question 29

When two events cannot occur at the same time,they are said to be mutually exclusive.

Question 30

If event A occurs,then its complement (A´)will also occur.

Question 31

If P(A)= .20 then the odds against event A's occurrence are 4 to 1.

Question 32

In a contingency table,the probability of the union of two events is found by taking the frequency of the intersection of the two events and dividing by the total.

Question 33

Insurance company life tables are an example of the classical (a priori)approach to probability.

Question 34

Events A and B are mutually exclusive when:

A) their joint probability is zero.
B) they are independent events.
C) P(A)P(B)= 0
D) P(A)P(B)= P(A | B)

Question 35

The general law of addition for probabilities says P(A or B)= P(A)P(B).

Question 36

The union of two events is all outcomes in either or both,while the intersection is only those events in both.

Question 37

If two events are complementary,then we know that:

A) the sum of their probabilities is one.
B) the joint probability of the two events is one.
C) their intersection has a nonzero probability.
D) they are independent events.

Question 38

The number of arrangements of sampled items drawn from a population is found with the formula for permutations (if order is important)or combinations (if order does not matter).

Question 39

P(A ∩ B)= .50 is an example of a joint probability.

Question 40

Baye's Theorem shows how to revise a prior probability to obtain a conditional or posterior probability when another event's occurrence is known.

Question 41

Oxnard Casualty wants to ensure that their e-mail server has 99.98 percent reliability.They will use several independent servers in parallel,each of which is 95 percent reliable.What is the smallest number of independent file servers that will accomplish the goal?

A) 1
B) 2
C) 3
D) 4

Question 42

Given the contingency table shown here,find P(A₂ | B₃).

A) .0685
B) .1893
C) .3721
D) .1842

Question 43

Given the contingency table shown here,find P(A₁ or B₂).

A) .0933
B) .3182
C) .0300
D) .3854

Question 44

Given the contingency table shown here,find P(A or M).

A) .2500
B) .7500
C) .6250
D) .1250

Question 45

Given the contingency table shown here,find the probability P(V´),that is,the probability of the complement of V.

A) .30
B) .50
C) .80
D) .15

Question 46

Given the contingency table shown here,find the probability that either event A₂ or event B₂ will occur.

A) .4454
B) .5054
C) .0600

Question 47

Within a given population,22 percent of the people are smokers,57 percent of the people are males,and 12 percent are males who smoke.If a person is chosen at random from the population,what is the probability that the selected person is either a male or a smoker?

A) .67
B) .79
C) .22
D) .43

Question 48

Given the contingency table shown here,find P(B).

A) .85
B) .25
C) .45
D) .22

Question 49

Given the contingency table shown here,find P(V).

A) .20
B) .40
C) .50
D) .80

Question 50

Regarding the rules of probability,which of the following statements is correct?

A) If A and B are independent events,then P(B)= P(A)P(B).
B) The sum of two mutually exclusive events is one.
C) The probability of A and its complement will sum to one.
D) If event A occurs,then its complement will also occur.

Question 51

Given the contingency table shown here,find P(V|W).

A) .4000
B) .0950
C) .2375
D) .5875

Question 52

Given the contingency table shown here,find P(A₂).

A) .1842
B) .1766
C) .8163
D) .0578

Question 53

Given the contingency table shown here,find P(A or B).

A) .25
B) .85
C) .60
D) .42

Question 54

Given the contingency table shown here,find P (A₃ ∩ B₂).

A) .3212
B) .2933
C) .0942
D) .1006

Question 55

Given the contingency table shown here,find P(A₁ ∩ A₂).

A) .00
B) .09
C) .28
D) .38

Question 56

Given the contingency table shown here,what is the probability that a randomly chosen employee who is under age 25 would be absent 2 or more days?

A) .625
B) .375
C) .150
D) .273

Question 57

Given the contingency table shown here,find P(W ∩ S).

A) .12
B) .30
C) .40
D) .58

Question 58

Information was collected on those who attended the opening of a new movie.The analysis found that 56 percent of the moviegoers were female,26 percent were under age 25,and 17 percent were females under the age of 25.Find the probability that a moviegoer is either female or under age 25.

A) .79
B) .82
C) .65
D) .50

Question 59

Given the contingency table shown here,find P(B|A).

A) .250
B) .555
C) .855
D) .625

Question 60

Find the probability that either event A or B occurs if the chance of A occurring is .5,the chance of B occurring is .3,and events A and B are independent.

A) .80
B) .15
C) .65
D) .85

Question 61

Given the contingency table shown here,what is the probability that a mother smoked during pregnancy or that she graduated from college?

A) .0111
B) .2591
C) .3861
D) .7850

Question 62

Given the contingency table shown here,find P(R ∩ L). Survey question: Do you plan on retiring or keep working when you turn 65?

A) .250
B) .315
C) .425
D) .850

Question 63

Given the contingency table shown here,what is the probability that a mother smoked during pregnancy if her education level was below high school?

A) .2385
B) .0907
C) .3503
D) .3804

Question 64

Given the contingency table shown here,find the probability that a mother with some college smoked during pregnancy.

A) .1078
B) .1746
C) .1601
D) .1117

Question 65

Given the contingency table shown here,what is the probability that a mother in the study smoked during pregnancy?

A) .2591
B) .3174
C) .5000
D) .7401

Question 66

Given the contingency table shown here,if a randomly chosen student attends school in an inner city location,what is the probability that it is a public school?

A) .189
B) .333
C) .500
D) .567

Question 67

Ramjac Company wants to set up k independent file servers,each capable of running the company's intranet.Each server has average "uptime" of 98 percent.What must k be to achieve 99.999 percent probability that the intranet will be "up"?

A) 1
B) 2
C) 3
D) 4

Question 68

Given the contingency table shown here,if a survey participant is selected at random,what is the probability he/she is an undergrad who favors the change to a quarter system?

A) .270
B) .135
C) .338
D) .756

Question 69

Given the contingency table shown here,find the probability that a randomly chosen employee is a line worker who plans to retire at age 65. Survey question: Do you plan on retiring or keep working when you turn 65?

A) .227
B) .419
C) .750
D) .315

Question 70

Given the contingency table shown here,if a faculty member is chosen at random,what is the probability he/she opposes the change to a quarter system?

A) .10
B) .25
C) .40
D) .60

Question 71

Given the contingency table shown here,what is the probability that a student attends a public school in a rural area?

A) .238
B) .714
C) .135
D) .567

Question 72

Given the contingency table shown here,does the decision to retire appear independent of the employee type? Survey question: Do you plan on retiring or keep working when you turn 65?

A) Yes.
B) No.

Question 73

Given the contingency table shown here,find P(E | F).

A) .160
B) .300
C) .340
D) .533

Question 74

Given the contingency table shown here,what is the probability that a mother smoked during pregnancy and had a college degree?

A) .0111
B) .0428
C) .0803
D) .2385

Question 75

Given the contingency table shown here,find P(W | M). Survey question: Do you plan on retiring or keep working when you turn 65?

A) .145
B) .250
C) .581
D) .687

Question 76

Given the contingency table shown here,what is the probability that a participant selected at random is a graduate student who opposes the change to a quarter system?

A) .135
B) .250
C) .375
D) .600

Question 77

Given the contingency table shown here,if a mother attended some college but did not have a degree,what is the probability that she did not smoke during her pregnancy?

A) .2736
B) .8399
C) .8752
D) .9197

Question 78

Given the contingency table shown here,if a randomly chosen student attends a religious school,what is the probability the location is rural?

A) .142
B) .162
C) .167
D) .333

Question 79

Given the contingency table shown here,find P(E).

A) .180
B) .300
C) .529
D) .641

Question 80

Given the contingency table shown here,find P(L or W). Survey question: Do you plan on retiring or keep working when you turn 65?

A) .750
B) .588
C) .435
D) .895