Deck 5: Randomness and Probability

Question 1

It has been reported that men are more likely than women to participate in online auctions.In a recent survey, 65% of respondents reported that they had participated in an online auction.In this same survey, 45% of respondents were men and 38% were men who had participated in online auctions.What is the probability that a respondent had participated in an online auction given that he is male?

A)0.38
B)0.84
C)0.62
D)0.45
E)0.55

Answer 1

0.84

Question 2

A recent survey of local cell phone retailers showed that of all cell phones sold last month, 64% had a camera, 28% had a music player and 22% had both.Which of the following statements about cell phones sold last month is true?

A)Having a camera and having a music player are mutually exclusive events.
B)The intersection of having a camera and having a music player is zero.
C)Having a camera and having a music player are independent events.
D)Having a camera and having a music player are disjoint events.
E)Having a camera and having a music player are not mutually exclusive events.

Answer 2

Having a camera and having a music player are not mutually exclusive events.

Question 3

As an incentive to get new customers, the local branch of a bank launched "bouncing for bucks." During this week long event, any customer opening a new checking account with the bank would have the opportunity to throw a bouncy rubber ball into a large box divided into squares.Each square was labeled with a dollar amount that would be deposited into his/her new checking account.The way the box was labeled is shown below.Out of the next three customers that come into the bank and play the game, what is the probability that at least one gets $50?

A)0.001
B)0.271
C)0.729
D)0.300
E)0.125

Answer 3

0.271

Question 4

As an incentive to get new customers, the local branch of a bank launched "bouncing for bucks." During this week long event, any customer opening a new checking account with the bank would have the opportunity to throw a bouncy rubber ball into a large box divided into squares.Each square was labeled with a dollar amount that would be deposited into his/her new checking account.The way the box was labeled is shown below.What is the probability that a customer does not get $50?

A)0.90
B)0.99
C)0.50
D)0.95
E)0.80

Question 5

A recent survey of local cell phone retailers showed that of all cell phones sold last month, 64% had a camera, 28% had a music player and 22% had both.The probability that a cell phone sold last month had a camera or a music player is ______________ .

A).22
B).70
C).92
D).30
E).08

Question 6

The option to buy extended warranties is commonplace with most electronics purchases.But does the type of purchase affect a consumer's willingness to pay extra for an extended warranty? Data for 420 consumers who purchased digital cameras and laptop computers from a leading electronics retailer are summarized in the table.The probability that a consumer does not purchase an extended warranty is _______________ .

A).07
B).42
C).58
D).17
E).83

Question 7

The option to buy extended warranties is commonplace with most electronics purchases.But does the type of purchase affect a consumer's willingness to pay extra for an extended warranty? Data for 420 consumers who purchased big screen TVs and laptop computers from a leading electronics retailer are summarized in the table.Which of the following statement is true?

A)The decision to purchase an extended warranty and type of electronics (big screen TV or laptop computer) purchased are independent.
B)The decision to purchase an extended warranty and type of electronics (big screen TV or laptop computer) purchased are mutually exclusive.
C)The decision to purchase an extended warranty and type of electronics (big screen TV or laptop computer) purchased are disjoint events.
D)The decision to purchase an extended warranty and type of electronics (big screen TV or laptop computer) purchased are not independent.
E)The decision to purchase an extended warranty and type of electronics (big screen TV or laptop computer) purchased are related.

Question 8

It has been reported that men are more likely than women to participate in online auctions.In a recent survey, 65% of respondents reported that they had participated in an online auction.In this same survey, 45% of respondents were men and 38% were men who had participated in online auctions.What is the probability that a respondent selected at random is female and has never participated in an online auction?

A)0.62
B)0.72
C)0.38
D)0.28
E)0.07

Question 9

A recent survey of local cell phone retailers showed that of all cell phones sold last month, 64% had a camera, 28% had a music player and 22% had both.The probability that a cell phone sold last month did not have either a camera or a music player is ______________ .

A).22
B).70
C).92
D).30
E).08

Question 10

During a promotion, Christina's department store offers a mailing "scratch a winner - discount savings." After customers select the items they wish to purchase, they scratch their discount sticker from the mailing to determine the discount they will receive.The scratch wheel is divided into 12 slices.Six slices are red and award a 10% discount, three slices are white and award a 20% discount, and two slices are blue and award a 40% discount.The remaining slice is gold and awards a 100% discount if the customer scratches that slice! The probability that a customer gets at least a 40% discount is ________________________ .

A)3/12
B)2/12
C).0625
D)9/12
E)10/12

Question 11

During a promotion, Christina's department store offers a mailing "scratch a winner - discount savings." After customers select the items they wish to purchase, they scratch their discount sticker from the mailing to determine the discount they will receive.The scratch wheel is divided into 12 slices.Six slices are red and award a 10% discount, three slices are white and award a 20% discount, and two slices are blue and award a 40% discount.The remaining slice is gold and awards a 100% discount if the customer scratches that slice! The probability that two customers in a row get a 20% discount is _____________ .

A)3/12
B)2/12
C).0625
D)9/12
E)10/12

Question 12

The option to buy extended warranties is commonplace with most electronics purchases.But does the type of purchase affect a consumer's willingness to pay extra for an extended warranty? Data for 420 consumers who purchased digital cameras and laptop computers from a leading electronics retailer are summarized in the table.The probability that a consumer purchases an extended warranty given that he/she has purchased a digital camera is ________________________ .

A).07
B).42
C).58
D).17
E).83

Question 13

As accounts manager in your company, you classify 75% of your customers as "good credit" and the rest as "risky credit" depending on their credit rating.Customers in the "risky" category allow their accounts to go overdue 50% of the time on average, whereas those in the "good" category allow their accounts to become overdue only 10% of the time.What percentage of overdue accounts are held by customers in the "risky credit" category?

A)20%
B)12.5%
C)93.75%
D)62.5%

Question 14

As an incentive to get new customers, the local branch of a bank launched "bouncing for bucks." During this week long event, any customer opening a new checking account with the bank would have the opportunity to throw a bouncy rubber ball into a large box divided into squares.Each square was labeled with a dollar amount that would be deposited into his/her new checking account.The way the box was labeled is shown below.What is the probability that three customers in a row do not get $50?

A)0.125
B)0.001
C)0.729
D)0.970
E)0.300

Question 15

Suncast Cable offers high definition (HD) cable TV, Internet and phone services to its customers.For those service issues that can be resolved by calling its technical support center, Suncast's goal is to have the problem solved within 30 minutes.In order to determine how well it is achieving this goal, they monitored calls to its technical support center over the last three months.The data compiled is shown in the table below.What is the probability that a call to the technical support center involved an issue with Internet service?

A)0.56
B)0.41
C)0.74
D)0.26
E)0.35

Question 16

The option to buy extended warranties is commonplace with most electronics purchases.But does the type of purchase affect a consumer's willingness to pay extra for an extended warranty? Data for 420 consumers who purchased digital cameras and laptop computers from a leading electronics retailer are summarized in the table.The probability that a consumer purchases a digital camera and an extended warranty is ________________________ .

A).07
B).42
C).58
D).17
E).83

Question 17

It has been reported that men are more likely than women to participate in online auctions.In a recent survey, 65% of respondents reported that they had participated in an online auction.In this same survey, 45% of respondents were men and 38% were men who had participated in online auctions.Which of the following is true?

A)Gender and participation in online auctions are independent.
B)Gender and participation in online auctions are disjoint.
C)The intersection of being male and participating in online auctions is zero.
D)Gender and participation in online auctions are not related.
E)Gender and participation in online auctions are dependent.

Question 18

Suncast Cable offers high definition (HD) cable TV, Internet and phone services to its customers.For those service issues that can be resolved by calling its technical support center, Suncast's goal is to have the problem solved within 30 minutes.In order to determine how well it is achieving this goal, they monitored calls to its technical support center over the last three months.The data compiled is shown in the table below.If Suncast wished to determine probabilities using these data, what type of probability would it be calculating?

A)Personal
B)Theoretical
C)Empirical
D)Model-based
E)Subjective

Question 19

During a promotion, Christina's department store offers a mailing "scratch a winner - discount savings." After customers select the items they wish to purchase, they scratch their discount sticker from the mailing to determine the discount they will receive.The scratch wheel is divided into 12 slices.Six slices are red and award a 10% discount, three slices are white and award a 20% discount, and two slices are blue and award a 40% discount.The remaining slice is gold and awards a 100% discount if the customer scratches that slice! The probability that a customer gets a 10% or 20% discount is ________________________ .

A)3/12
B)2/12
C).0625
D)9/12
E)10/12

Question 20

As an incentive to get new customers, the local branch of a bank launched "bouncing for bucks." During this week long event, any customer opening a new checking account with the bank would have the opportunity to throw a bouncy rubber ball into a large box divided into squares.Each square was labeled with a dollar amount that would be deposited into his/her new checking account.The way the box was labeled is shown below.What is the probability that a customer gets $50?

A)0.10
B)0.01
C)0.50
D)0.05
E)0.20

Question 21

Suncast Cable offers high definition (HD) cable TV, Internet and phone services to its customers.For those service issues that can be resolved by calling its technical support center, Suncast's goal is to have the problem solved within 30 minutes.In order to determine how well it is achieving this goal, they monitored calls to its technical support center over the last three months.The data compiled is shown in the table below.What is the probability that a call to the technical support center involved an issue with Internet service or was not resolved within 30 minutes?

A)0.91
B)0.55
C)0.35
D)0.76
E)0.14

Question 22

A manufacturer claims that its drug test will detect steroid use (that is, show positive for an athlete who uses steroids) 95% of the time.Further, 15% of all steroid-free individuals also test positive.10% of the rugby team members use steroids.Your friend on the rugby team has just tested positive.The probability that he uses steroids is ________________________ .

A)0.4130
B)0.8636
C)0.0950
D)0.2300