Deck 4: Basic Probability

Question 1

If two events are collectively exhaustive, what is the probability that both occur at the same time?

A) 0.
B) 0.50.
C) 1.00.
D) Cannot be determined from the information given.

Answer 1

D

Question 2

If event A and event B cannot occur at the same time, then events A and B are said to be

A) mutually exclusive.
B) independent.
C) collectively exhaustive.
D) None of the above.

Answer 2

A

Question 3

If two events are independent, what is the probability that they both occur?

A) 0.
B) 0.50.
C) 1.00.
D) Cannot be determined from the information given.

Answer 3

D

Question 4

If two events are mutually exclusive, what is the probability that both occur at the same time?

A) 0.
B) 0.50.
C) 1.00.
D) Cannot be determined from the information given.

Question 5

If two events are mutually exclusive and collectively exhaustive, what is the probability that one or the other occurs?

A) 0.
B) 0.50.
C) 1.00.
D) Cannot be determined from the information given.

Question 6

If two events are mutually exclusive, what is the probability that one or the other occurs?

A) 0.
B) 0.50.
C) 1.00.
D) Cannot be determined from the information given.

Question 7

If two equally likely events A and B are collectively exhaustive, what is the probability that event A occurs?

A) 0.
B) 0.50.
C) 1.00.
D) Cannot be determined from the information given.

Question 8

If either event A or event B must occur, then events A and B are said to be

A) mutually exclusive.
B) independent.
C) collectively exhaustive.
D) None of the above.

Question 9

Simple probability is also called

A) marginal probability.
B) joint probability.
C) conditional probability.
D) Bayes' theorem.

Question 10

If two events are mutually exclusive and collectively exhaustive, what is the probability that both occur?

A) 0.
B) 0.50.
C) 1.00.
D) Cannot be determined from the information given.

Question 11

If two events are collectively exhaustive, what is the probability that one or the other occurs?

A) 0.
B) 0.50.
C) 1.00.
D) Cannot be determined from the information given.

Question 12

A business venture can result in the following outcomes (with their corresponding chance of occurring in parentheses): Highly Successful (10%), Successful (25%), Break Even (25%),
Disappointing (20%), and Highly Disappointing (?). If these are the only outcomes possible for
The business venture, what is the chance that the business venture will be considered Highly
Disappointing?

A) 10%
B) 15%
C) 20%
D) 25%

Question 13

If two equally likely events A and B are mutually exclusive, what is the probability that event A occurs?

A) 0.
B) 0.50.
C) 1.00.
D) Cannot be determined from the information given.

Question 14

All the events in the sample space that are not part of the specified event are called

A) simple events.
B) joint events.
C) the sample space.
D) the complement of the event.

Question 15

Selection of raffle tickets from a large bowl is an example of

A) simple probability.
B) sampling without replacement.
C) subjective probability.
D) None of the above.

Question 16

If the outcome of event A is not affected by event B, then events A and B are said to be

A) mutually exclusive.
B) independent.
C) collectively exhaustive.
D) None of the above.

Question 17

The collection of all possible events is called

A) a simple probability.
B) a sample space.
C) a joint probability.
D) the null set.

Question 18

If events A and B are mutually exclusive and collectively exhaustive, what is the probability that event A occurs?

A) 0.
B) 0.50.
C) 1.00.
D) Cannot be determined from the information given.

Question 19

When using the general multiplication rule, P(A and B) is equal to

Question 20

If two equally likely events A and B are mutually exclusive and collectively exhaustive, what is the probability that event A occurs?

A) 0.
B) 0.50.
C) 1.00.
D) Cannot be determined from the information given.

Question 21

According to a survey of American households, the probability that the residents own 2 cars if annual household income is over $50,000 is 80%. Of the households surveyed, 60% had incomes
Over $50,000 and 70% had 2 cars. The probability that the residents of a household own 2 cars
And have an income over $50,000 a year is:

A) 0.12
B) 0.18
C) 0.22
D) 0.48

Question 22

The probability that house sales will increase in the next 6 months is estimated to be 0.25. The probability that the interest rates on housing loans will go up in the same period is estimated to be
0)74. The probability that house sales or interest rates will go up during the next 6 months is
Estimated to be 0.89. The probability that both house sales and interest rates will increase during
The next 6 months is:

A) 0.10
B) 0.185
C) 0.705
D) 0.90

Question 23

The probability that house sales will increase in the next 6 months is estimated to be 0.25. The probability that the interest rates on housing loans will go up in the same period is estimated to be
0)74. The probability that house sales or interest rates will go up during the next 6 months is
Estimated to be 0.89. The probability that neither house sales nor interest rates will increase
During the next 6 months is:

A) 0.11
B) 0.195
C) 0.89
D) 0.90

Question 24

The probability that house sales will increase in the next 6 months is estimated to be 0.25. The probability that the interest rates on housing loans will go up in the same period is estimated to be
0)74. The probability that house sales or interest rates will go up during the next 6 months is
Estimated to be 0.89. The events increase in house sales and no increase in house sales in the next
6 months are

A) independent.
B) mutually exclusive.
C) collectively exhaustive.
D) (b) and (c)

Question 25

The employees of a company were surveyed on questions regarding their educational background (college degree or no college degree) and marital status (single or married). Of the 600
Employees, 400 had college degrees, 100 were single, and 60 were single college graduates. The
Probability that an employee of the company is married and has a college degree is:

A) 0.0667
B) 0.567
C) 0.667
D) 0.833

Question 26

The probability that a new advertising campaign will increase sales is assessed as being 0.80. The probability that the cost of developing the new ad campaign can be kept within the original
Budget allocation is 0.40. Assuming that the two events are independent, the probability that the
Cost is kept within budget or the campaign will increase sales is:

A) 0.20
B) 0.32
C) 0.68
D) 0.88

Question 27

The probability that a new advertising campaign will increase sales is assessed as being 0.80. The probability that the cost of developing the new ad campaign can be kept within the original
Budget allocation is 0.40. Assuming that the two events are independent, the probability that the
Cost is kept within budget and the campaign will increase sales is:

A) 0.20
B) 0.32
C) 0.40
D) 0.88

Question 28

The employees of a company were surveyed on questions regarding their educational background (college degree or no college degree) and marital status (single or married). Of the 600
Employees, 400 had college degrees, 100 were single, and 60 were single college graduates. The
Probability that an employee of the company is single or has a college degree is:

A) 0.10
B) 0.25
C) 0.667
D) 0.733

Question 29

According to a survey of American households, the probability that the residents own 2 cars if annual household income is over $50,000 is 80%. Of the households surveyed, 60% had incomes
Over $50,000 and 70% had 2 cars. The probability that the residents of a household own 2 cars
And have an income less than or equal to $50,000 a year is:

A) 0.12
B) 0.18
C) 0.22
D) 0.48

Question 30

The probability that house sales will increase in the next 6 months is estimated to be 0.25. The probability that the interest rates on housing loans will go up in the same period is estimated to be
0)74. The probability that house sales or interest rates will go up during the next 6 months is
Estimated to be 0.89. The events increase in house sales and increase in interest rates in the next 6
Months are

A) independent.
B) mutually exclusive.
C) collectively exhaustive.
D) None of the above.

Question 31

A company has 2 machines that produce widgets. An older machine produces 23% defective widgets, while the new machine produces only 8% defective widgets. In addition, the new
Machine produces 3 times as many widgets as the older machine does. Given that a widget was
Produced by the new machine, what is the probability it is not defective?

A) 0.06
B) 0.50
C) 0.92
D) 0.94

Question 32

The probability that a new advertising campaign will increase sales is assessed as being 0.80. The probability that the cost of developing the new ad campaign can be kept within the original
Budget allocation is 0.40. Assuming that the two events are independent, the probability that
Neither the cost is kept within budget nor the campaign will increase sales is:

A) 0.12
B) 0.32
C) 0.68
D) 0.88

Question 33

A company has 2 machines that produce widgets. An older machine produces 23% defective widgets, while the new machine produces only 8% defective widgets. In addition, the new
Machine produces 3 times as many widgets as the older machine does. What is the probability
That a randomly chosen widget produced by the company is defective?

A) 0.078
B) 0.1175
C) 0.156
D) 0.310

Question 34

The probability that a new advertising campaign will increase sales is assessed as being 0.80. The probability that the cost of developing the new ad campaign can be kept within the original
Budget allocation is 0.40. Assuming that the two events are independent, the probability that the
Cost is not kept within budget or the campaign will not increase sales is:

A) 0.12
B) 0.32
C) 0.68
D) 0.88

Question 35

SCENARIO 4-1
Mothers Against Drunk Driving is a very visible group whose main focus is to educate the public
about the harm caused by drunk drivers. A study was recently done that emphasized the problem we
all face with drinking and driving. Four hundred accidents that occurred on a Saturday night were
analyzed. Two items noted were the number of vehicles involved and whether alcohol played a role
in the accident. The numbers are shown below: $$\begin{array} { c | | c c c | c } & { \text { Number of Vehicles } } \\& { \text { Involved } } \\\text { Did alcohol play a role? } & \mathbf { 1 } & \mathbf { 2 } & \mathbf { 3 } & \text { Totals } \\ \text { Yes } & 50 & 100 & 20 & 170 \\\text { No } & 25 & 175 & 30 & 230 \\\hline \text { Totals } & 75 & 275 & 50 & 400\end{array}$$

-Referring to Scenario 4-1, what proportion of accidents involved more than one vehicle?

A) 50/400 or 12.5%
B) 75/400 or 18.75%
C) 275/400 or 68.75%
D) 325/400 or 81.25%

Question 36

A survey of banks revealed the following distribution for the interest rate being charged on a home loan (based on a 30-year mortgage with a 10% down payment) on a certain date in the past. $$\begin{array} { c | c | c | c | c | c } \text { Interest Rate } & \begin{array} { c } 3.20 \% \\\text { to } \\3.29 \%\end{array} & \begin{array} { c } 3.30 \% \\\text { to } \\3.39 \%\end{array} & \begin{array} { c } 3.40 \% \\\text { to } \\3.49 \%\end{array} & \begin{array} { c } 3.50 \% \\\text { to } \\3.59 \%\end{array} & \begin{array} { c } 3.60 \% \\\text { and } \\\text { above }\end{array} \\\hline \text { Probability } & 0.12 & 0.23 & 0.24 & 0.35 & 0.06\end{array}$$ If a bank is selected at random from this distribution, what is the chance that the interest rate charged
On a home loan will exceed 3.49%?

A) 0.06
B) 0.41
C) 0.59
D) 1.00

Question 37

The probability that house sales will increase in the next 6 months is estimated to be 0.25. The probability that the interest rates on housing loans will go up in the same period is estimated to be
0)74. The probability that house sales or interest rates will go up during the next 6 months is
Estimated to be 0.89. The probability that house sales will increase but interest rates will not
During the next 6 months is:

A) 0.065
B) 0.15
C) 0.51
D) 0.89

Question 38

According to a survey of American households, the probability that the residents own 2 cars if annual household income is over $50,000 is 80%. Of the households surveyed, 60% had incomes
Over $50,000 and 70% had 2 cars. The probability that the residents do not own 2 cars if annual
Household income is not over $50,000 is:

A) 0.12
B) 0.18
C) 0.45
D) 0.70

Question 39

The employees of a company were surveyed on questions regarding their educational background (college degree or no college degree) and marital status (single or married). Of the 600
Employees, 400 had college degrees, 100 were single, and 60 were single college graduates. The
Probability that an employee of the company does not have a college degree is:

A) 0.10
B) 0.33
C) 0.67
D) 0.75

Question 40

According to a survey of American households, the probability that the residents own 2 cars if annual household income is over $50,000 is 80%. Of the households surveyed, 60% had incomes
Over $50,000 and 70% had 2 cars. The probability that the residents of a household do not own 2
Cars and have an income over $50,000 a year is:

A) 0.12
B) 0.18
C) 0.22
D) 0.48

Question 41

If either A or B must occur they are called mutually exclusive.

Question 42

SCENARIO 4-2
An alcohol awareness task force at a Big-Ten university sampled 200 students after the midterm to
ask them whether they went bar hopping the weekend before the midterm or spent the weekend
studying, and whether they did well or poorly on the midterm. The following result was obtained.
Referring to Scenario 4-2, what is the probability that a randomly selected student did well on the midterm or went bar hopping the weekend before the midterm?

Question 43

SCENARIO 4-2
An alcohol awareness task force at a Big-Ten university sampled 200 students after the midterm to
ask them whether they went bar hopping the weekend before the midterm or spent the weekend
studying, and whether they did well or poorly on the midterm. The following result was obtained. $$\begin{array} { | l | l | l | } \hline & \text { Did Well on Midterm } & \text { Did Poorly on Midterm } \\\hline \text { Studying for Exam } & 80 & 20 \\\hline \text { Went Bar Hopping } & 30 & 70 \\\hline\end{array}$$

-Referring to Scenario 4-2, the events "Did Well on Midterm" and "Studying for Exam" are

A) dependent.
B) mutually exclusive.
C) collective exhaustive.
D) None of the above.

Question 44

SCENARIO 4-1
Mothers Against Drunk Driving is a very visible group whose main focus is to educate the public
about the harm caused by drunk drivers. A study was recently done that emphasized the problem we
all face with drinking and driving. Four hundred accidents that occurred on a Saturday night were
analyzed. Two items noted were the number of vehicles involved and whether alcohol played a role
in the accident. The numbers are shown below: $$\begin{array} { c | | c c c | c } & { \text { Number of Vehicles } } \\& { \text { Involved } } \\\text { Did alcohol play a role? } & \mathbf { 1 } & \mathbf { 2 } & \mathbf { 3 } & \text { Totals } \\ \text { Yes } & 50 & 100 & 20 & 170 \\\text { No } & 25 & 175 & 30 & 230 \\\hline \text { Totals } & 75 & 275 & 50 & 400\end{array}$$

-Referring to Scenario 4-1, given that alcohol was not involved, what proportion of the accidents were single vehicle?

A) 50/75 or 66.67%
B) 25/230 or 10.87%
C) 50/170 or 29.41%
D) 25/75 or 33.33%

Question 45

SCENARIO 4-1
Mothers Against Drunk Driving is a very visible group whose main focus is to educate the public
about the harm caused by drunk drivers. A study was recently done that emphasized the problem we
all face with drinking and driving. Four hundred accidents that occurred on a Saturday night were
analyzed. Two items noted were the number of vehicles involved and whether alcohol played a role
in the accident. The numbers are shown below: $$\begin{array} { c | | c c c | c } & { \text { Number of Vehicles } } \\& { \text { Involved } } \\\text { Did alcohol play a role? } & \mathbf { 1 } & \mathbf { 2 } & \mathbf { 3 } & \text { Totals } \\ \text { Yes } & 50 & 100 & 20 & 170 \\\text { No } & 25 & 175 & 30 & 230 \\\hline \text { Totals } & 75 & 275 & 50 & 400\end{array}$$

-Referring to Scenario 4-1, given that multiple vehicles were involved, what proportion of accidents involved alcohol?

A) 120/170 or 70.59%
B) 120/230 or 52.17%
C) 120/325 or 36.92%
D) 120/400 or 30%

Question 46

If P(A) = 0.4 and P(B) = 0.6, then A and B must be collectively exhaustive.

Question 47

SCENARIO 4-2
An alcohol awareness task force at a Big-Ten university sampled 200 students after the midterm to
ask them whether they went bar hopping the weekend before the midterm or spent the weekend
studying, and whether they did well or poorly on the midterm. The following result was obtained. $$\begin{array} { | l | l | l | } \hline & \text { Did Well on Midterm } & \text { Did Poorly on Midterm } \\\hline \text { Studying for Exam } & 80 & 20 \\\hline \text { Went Bar Hopping } & 30 & 70 \\\hline\end{array}$$

-Referring to Scenario 4-2, what is the probability that a randomly selected student did well on the midterm and also went bar hopping the weekend before the midterm?

A) 30/200 or 15%
B) (80+30)/200 or 55%
C) (30+70)/200 or 50%
D) (80+30+70)/200 or 90%

Question 48

If P(A) = 0.4 and P(B) = 0.6, then A and B must be mutually exclusive.

Question 49

SCENARIO 4-1
Mothers Against Drunk Driving is a very visible group whose main focus is to educate the public
about the harm caused by drunk drivers. A study was recently done that emphasized the problem we
all face with drinking and driving. Four hundred accidents that occurred on a Saturday night were
analyzed. Two items noted were the number of vehicles involved and whether alcohol played a role
in the accident. The numbers are shown below: $$\begin{array} { c | | c c c | c } & { \text { Number of Vehicles } } \\& { \text { Involved } } \\\text { Did alcohol play a role? } & \mathbf { 1 } & \mathbf { 2 } & \mathbf { 3 } & \text { Totals } \\ \text { Yes } & 50 & 100 & 20 & 170 \\\text { No } & 25 & 175 & 30 & 230 \\\hline \text { Totals } & 75 & 275 & 50 & 400\end{array}$$

-Referring to Scenario 4-1, what proportion of accidents involved alcohol or a single vehicle?

A) 25/400 or 6.25%
B) 50/400 or 12.5%
C) 195/400 or 48.75%
D) 245/400 or 61.25%

Question 50

If A and B cannot occur at the same time they are called mutually exclusive.

Question 51

The collection of all the possible events is called a sample space.

Question 52

SCENARIO 4-1
Mothers Against Drunk Driving is a very visible group whose main focus is to educate the public
about the harm caused by drunk drivers. A study was recently done that emphasized the problem we
all face with drinking and driving. Four hundred accidents that occurred on a Saturday night were
analyzed. Two items noted were the number of vehicles involved and whether alcohol played a role
in the accident. The numbers are shown below: $$\begin{array} { c | | c c c | c } & { \text { Number of Vehicles } } \\& { \text { Involved } } \\\text { Did alcohol play a role? } & \mathbf { 1 } & \mathbf { 2 } & \mathbf { 3 } & \text { Totals } \\ \text { Yes } & 50 & 100 & 20 & 170 \\\text { No } & 25 & 175 & 30 & 230 \\\hline \text { Totals } & 75 & 275 & 50 & 400\end{array}$$

-Referring to Scenario 4-1, given alcohol was involved, what proportion of accidents involved a single vehicle?

A) 50/75 or 66.67%
B) 50/170 or 29.41%
C) 120/170 or 70.59%
D) 120/400 or 30%

Question 53

When A and B are mutually exclusive, P(A or B) can be found by adding P(A) and
P(B).

Question 54

SCENARIO 4-2
An alcohol awareness task force at a Big-Ten university sampled 200 students after the midterm to
ask them whether they went bar hopping the weekend before the midterm or spent the weekend
studying, and whether they did well or poorly on the midterm. The following result was obtained. $$\begin{array} { | l | l | l | } \hline & \text { Did Well on Midterm } & \text { Did Poorly on Midterm } \\\hline \text { Studying for Exam } & 80 & 20 \\\hline \text { Went Bar Hopping } & 30 & 70 \\\hline\end{array}$$

-Referring to Scenario 4-2, the events "Did Well on Midterm" and "Studying for Exam" are

A) not dependent.
B) not mutually exclusive.
C) collective exhaustive.
D) None of the above.

Question 55

SCENARIO 4-1
Mothers Against Drunk Driving is a very visible group whose main focus is to educate the public
about the harm caused by drunk drivers. A study was recently done that emphasized the problem we
all face with drinking and driving. Four hundred accidents that occurred on a Saturday night were
analyzed. Two items noted were the number of vehicles involved and whether alcohol played a role
in the accident. The numbers are shown below: $$\begin{array} { c | | c c c | c } & { \text { Number of Vehicles } } \\& { \text { Involved } } \\\text { Did alcohol play a role? } & \mathbf { 1 } & \mathbf { 2 } & \mathbf { 3 } & \text { Totals } \\ \text { Yes } & 50 & 100 & 20 & 170 \\\text { No } & 25 & 175 & 30 & 230 \\\hline \text { Totals } & 75 & 275 & 50 & 400\end{array}$$

-Referring to Scenario 4-1, given that alcohol was not involved, what proportion of the accidents were multiple vehicle?

A) 50/170 or 29.41%
B) 120/170 or 70.59%
C) 205/230 or 89.13%
D) 25/230 or 10.87%

Question 56

SCENARIO 4-2
An alcohol awareness task force at a Big-Ten university sampled 200 students after the midterm to
ask them whether they went bar hopping the weekend before the midterm or spent the weekend
studying, and whether they did well or poorly on the midterm. The following result was obtained. $$\begin{array} { | l | l | l | } \hline & \text { Did Well on Midterm } & \text { Did Poorly on Midterm } \\\hline \text { Studying for Exam } & 80 & 20 \\\hline \text { Went Bar Hopping } & 30 & 70 \\\hline\end{array}$$

-Referring to Scenario 4-2, what is the probability that a randomly selected student who went bar hopping did well on the midterm?

A) 30/100 or 30%
B) 30/110 or 27.27%
C) 30/200 or 15%
D) (100/200)*(110/200) or 27.50%

Question 57

If either A or B must occur they are called collectively exhaustive.

Question 58

SCENARIO 4-1
Mothers Against Drunk Driving is a very visible group whose main focus is to educate the public
about the harm caused by drunk drivers. A study was recently done that emphasized the problem we
all face with drinking and driving. Four hundred accidents that occurred on a Saturday night were
analyzed. Two items noted were the number of vehicles involved and whether alcohol played a role
in the accident. The numbers are shown below: $$\begin{array} { c | | c c c | c } & { \text { Number of Vehicles } } \\& { \text { Involved } } \\\text { Did alcohol play a role? } & \mathbf { 1 } & \mathbf { 2 } & \mathbf { 3 } & \text { Totals } \\ \text { Yes } & 50 & 100 & 20 & 170 \\\text { No } & 25 & 175 & 30 & 230 \\\hline \text { Totals } & 75 & 275 & 50 & 400\end{array}$$

-Referring to Scenario 4-1, given that 3 vehicles were involved, what proportion of accidents involved alcohol?

A) 20/30 or 66.67%
B) 20/50 or 40%
C) 20/170 or 11.77%
D) 20/400 or 5%

Question 59

SCENARIO 4-2
An alcohol awareness task force at a Big-Ten university sampled 200 students after the midterm to
ask them whether they went bar hopping the weekend before the midterm or spent the weekend
studying, and whether they did well or poorly on the midterm. The following result was obtained. $$\begin{array} { | l | l | l | } \hline & \text { Did Well on Midterm } & \text { Did Poorly on Midterm } \\\hline \text { Studying for Exam } & 80 & 20 \\\hline \text { Went Bar Hopping } & 30 & 70 \\\hline\end{array}$$

-Referring to Scenario 4-2, the events "Did Well on Midterm" and "Did Poorly on Midterm" are

A) dependent.
B) mutually exclusive.
C) collective exhaustive.
D) All of the above.

Question 60

SCENARIO 4-1
Mothers Against Drunk Driving is a very visible group whose main focus is to educate the public
about the harm caused by drunk drivers. A study was recently done that emphasized the problem we
all face with drinking and driving. Four hundred accidents that occurred on a Saturday night were
analyzed. Two items noted were the number of vehicles involved and whether alcohol played a role
in the accident. The numbers are shown below: $$\begin{array} { c | | c c c | c } & { \text { Number of Vehicles } } \\& { \text { Involved } } \\\text { Did alcohol play a role? } & \mathbf { 1 } & \mathbf { 2 } & \mathbf { 3 } & \text { Totals } \\ \text { Yes } & 50 & 100 & 20 & 170 \\\text { No } & 25 & 175 & 30 & 230 \\\hline \text { Totals } & 75 & 275 & 50 & 400\end{array}$$

-Referring to Scenario 4-1, what proportion of accidents involved alcohol and a single vehicle?

A) 25/400 or 6.25%
B) 50/400 or 12.5%
C) 195/400 or 48.75%
D) 245/400 or 61.25%

Question 61

SCENARIO 4-4
Suppose that patrons of a restaurant were asked whether they preferred water or whether they
preferred soda. 70% said that they preferred water. 60% of the patrons were male. 80% of the males
preferred water.
Referring to Scenario 4-4, the probability a randomly selected patron prefers soda is __________.

Question 62

SCENARIO 4-3
A survey is taken among customers of a fast-food restaurant to determine preference for hamburger or
chicken. Of 200 respondents selected, 75 were children and 125 were adults. 120 preferred hamburger
and 80 preferred chicken. 55 of the children preferred hamburger.
Referring to Scenario 4-3, the probability that a randomly selected individual is a child or prefers
hamburger is __________.

Question 63

If P(A and B) = 0, then A and B must be mutually exclusive.

Question 64

Suppose A and B are events where P(A) = 0.4, P(B) = 0.5, and P(A and B) = 0.1. Then P(A|B) =
__________.

Question 65

SCENARIO 4-3
A survey is taken among customers of a fast-food restaurant to determine preference for hamburger or
chicken. Of 200 respondents selected, 75 were children and 125 were adults. 120 preferred hamburger
and 80 preferred chicken. 55 of the children preferred hamburger.
Referring to Scenario 4-3, the probability that a randomly selected individual is an adult or a child
is __________.

Question 66

Suppose A and B are independent events where P(A) = 0.4 and P(B) = 0.5. Then P(A and B) =
__________.

Question 67

SCENARIO 4-3
A survey is taken among customers of a fast-food restaurant to determine preference for hamburger or
chicken. Of 200 respondents selected, 75 were children and 125 were adults. 120 preferred hamburger
and 80 preferred chicken. 55 of the children preferred hamburger.
Referring to Scenario 4-3, the probability that a randomly selected individual is an adult is
__________.

Question 68

SCENARIO 4-3
A survey is taken among customers of a fast-food restaurant to determine preference for hamburger or
chicken. Of 200 respondents selected, 75 were children and 125 were adults. 120 preferred hamburger
and 80 preferred chicken. 55 of the children preferred hamburger.
Referring to Scenario 4-3, assume we know the person is a child. The probability that this
individual prefers hamburger is __________.

Question 69

Suppose A and B are events where P(A) = 0.4, P(B) = 0.5, and P(A and B) = 0.1. Then P(A or B)
= __________.

Question 70

Suppose A and B are events where P(A) = 0.4, P(B) = 0.5, and P(A and B) = 0.1. Then P(B|A) =
__________.

Question 71

SCENARIO 4-3
A survey is taken among customers of a fast-food restaurant to determine preference for hamburger or
chicken. Of 200 respondents selected, 75 were children and 125 were adults. 120 preferred hamburger
and 80 preferred chicken. 55 of the children preferred hamburger.
Referring to Scenario 4-3, the probability that a randomly selected individual is a child and
prefers chicken is __________.

Question 72

SCENARIO 4-3
A survey is taken among customers of a fast-food restaurant to determine preference for hamburger or
chicken. Of 200 respondents selected, 75 were children and 125 were adults. 120 preferred hamburger
and 80 preferred chicken. 55 of the children preferred hamburger.
Referring to Scenario 4-3, the probability that a randomly selected individual is an adult and
prefers chicken is __________.

Question 73

If P(A and B) = 0, then A and B must be collectively exhaustive.

Question 74

Suppose A and B are independent events where P(A) = 0.4 and P(B) = 0.5. Then P(A or B) =
__________.

Question 75

If P(A and B) = 1, then A and B must be collectively exhaustive.

Question 76

If P(A or B) = 1.0, then A and B must be collectively exhaustive.

Question 77

If P(A and B) = 1, then A and B must be mutually exclusive.

Question 78

Suppose A and B are mutually exclusive events where P(A) = 0.4 and P(B) = 0.5. Then P(A or B)
= __________.

Question 79

If P(A or B) = 1.0, then A and B must be mutually exclusive.

Question 80

Suppose A and B are mutually exclusive events where P(A) = 0.4 and P(B) = 0.5. Then P(A and
B) = __________.