Question 1

Customer arrivals per unit of time would tend to follow a binomial distribution.

Accepted Answer

A) True 
 B)False

Question 2

On Saturday morning,calls arrive at TicketMaster at a rate of 108 calls per hour.What is the probability of fewer than three calls in a randomly chosen minute?

Accepted Answer

A)  .1607 
B)  .8913 
C)  .2678 
D)  .7306 
A)  .1607 
B)  .8913 
C)  .2678 
D)  .7306

Question 3

Arrival of cars per minute at a toll booth may be characterized by the Poisson distribution if:

Accepted Answer

A)  the arrivals are independent. 
B)  no more than one arrival can occur in a minute. 
C)  there is only one lane leading to the booth. 
D)  the mean arrival rate is at least 30. 
A)  the arrivals are independent. 
B)  no more than one arrival can occur in a minute. 
C)  there is only one lane leading to the booth. 
D)  the mean arrival rate is at least 30.

Question 4

A project has three independent stages that must be completed in sequence.The time to complete each stage is a random variable.The expected times to complete the stages are μ1 = 23,μ2 = 11,μ3 = 17.The expected project completion time is:

Accepted Answer

A)  51. 
B)  23. 
C)  40. 
A)  51. 
B)  23. 
C)  40.

Question 5

If the probability of success is .25,what is the probability of obtaining the first success within the first three trials?

Accepted Answer

A)  .4218 
B)  .5781 
C)  .1406 
D)  .2228 
A)  .4218 
B)  .5781 
C)  .1406 
D)  .2228

Question 6

Which model best describes the number of births in a hospital until the first twins are delivered?

Accepted Answer

A)  Binomial 
B)  Poisson 
C)  Hypergeometric 
D)  Geometric 
A)  Binomial 
B)  Poisson 
C)  Hypergeometric 
D)  Geometric

Question 7

For which binomial distribution would a Poisson approximation not be acceptable?

Accepted Answer

A)  n = 35,π = 0.07 
B)  n = 95,π = 0.01 
C)  n = 80,π = 0.02 
D)  n = 50,π = 0.03 
A)  n = 35,π = 0.07 
B)  n = 95,π = 0.01 
C)  n = 80,π = 0.02 
D)  n = 50,π = 0.03

Question 8

The coefficient of variation for a Poisson distribution with λ = 5 is:

Accepted Answer

A)  35.2 percent. 
B)  58.9 percent. 
C)  44.7 percent. 
D)  31.1 percent. 
A)  35.2 percent. 
B)  58.9 percent. 
C)  44.7 percent. 
D)  31.1 percent.

Question 9

On a particular day,112 of 280 passengers on a particular DTW-LAX flight used the e-ticket check-in kiosk to obtain boarding passes.In a random sample of eight passengers,use the binomial model to find the approximate hypergeometric probability that four will have used the e-ticket check-in kiosk to obtain boarding passes.

Accepted Answer

A)  .2322 
B)  .8263 
C)  .2926 
D)  .5613 
A)  .2322 
B)  .8263 
C)  .2926 
D)  .5613

Question 10

The number of people injured in rafting expeditions on the Colorado River on a randomly chosen Thursday in August is best described by which model?

Accepted Answer

A)  Binomial 
B)  Poisson 
C)  Hypergeometric 
D)  Geometric 
A)  Binomial 
B)  Poisson 
C)  Hypergeometric 
D)  Geometric

Question 11

If X is a discrete uniform random variable ranging from 0 to 12,find P(X ≥ 10).

Accepted Answer

A)  .1126 
B)  .1666 
C)  .2308 
D)  .2500 
A)  .1126 
B)  .1666 
C)  .2308 
D)  .2500

Question 12

An example of a geometric random variable is the number of pine trees with pine beetle infestation in a random sample of 15 pine trees in Colorado.

Accepted Answer

A) True 
 B)False

Question 13

Which of the following characterizes a Bernoulli process?

Accepted Answer

A)  A random experiment that has only two outcomes. 
B)  The probability of "success" varies with each trial. 
C)  Either outcome has the same chance of occurrence. 
D)  The "success" must be a desirable outcome. 
A)  A random experiment that has only two outcomes. 
B)  The probability of "success" varies with each trial. 
C)  Either outcome has the same chance of occurrence. 
D)  The "success" must be a desirable outcome.

Question 14

On a Sunday in April,dog bite victims arrive at Carver Memorial Hospital at a historical rate of 0.6 victim per day.On a given Sunday in April,what is the probability that exactly two dog bite victims will arrive?

Accepted Answer

A)  .0875 
B)  .0902 
C)  .0988 
D)  .0919 
A)  .0875 
B)  .0902 
C)  .0988 
D)  .0919

Question 15

The probability that a certain daily flight's departure from ORD to LAX is delayed is .02.Over six months,this flight departs 180 times.What is the approximate Poisson probability that it will be delayed fewer than 2 times?

Accepted Answer

A)  .4471 
B)  .3028 
C)  .1257 
D)  .1771 
A)  .4471 
B)  .3028 
C)  .1257 
D)  .1771

Question 16

The Poisson distribution describes the number of occurrences within a randomly chosen unit of time or space.

Accepted Answer

A) True 
 B)False

Question 17

If 90 percent of automobiles in Orange County have both headlights working,what is the probability that in a sample of eight automobiles,at least seven will have both headlights working?

Accepted Answer

A)  .6174 
B)  .3826 
C)  .8131 
D)  .1869 
A)  .6174 
B)  .3826 
C)  .8131 
D)  .1869

Question 18

A stock portfolio consists of two stocks X and Y.Their daily closing prices are correlated random variables with variances σX2 = 3.51 and σY2 = 5.22,and covariance σXY = -1.55.What is the standard deviation of the sum of the closing prices of these two stocks?

Accepted Answer

A)  5.63 
B)  7.18 
C)  8.73 
D)  2.68 
A)  5.63 
B)  7.18 
C)  8.73 
D)  2.68

Question 19

Cars are arriving at a toll booth at a rate of four per minute.What is the probability that exactly eight cars will arrive in the next two minutes?

Accepted Answer

A)  0.0349 
B)  0.1396 
C)  0.9666 
D)  0.0005 
A)  0.0349 
B)  0.1396 
C)  0.9666 
D)  0.0005

Question 20

The hypergeometric distribution is skewed right.

Accepted Answer

A) True 
 B)False

Customer arrivals per unit of time would tend to follow a binomial distribution.

On Saturday morning,calls arrive at TicketMaster at a rate of 108 calls per hour.What is the probability of fewer than three calls in a randomly chosen minute?

Arrival of cars per minute at a toll booth may be characterized by the Poisson distribution if:

A project has three independent stages that must be completed in sequence.The time to complete each stage is a random variable.The expected times to complete the stages are μ₁ = 23,μ₂ = 11,μ₃ = 17.The expected project completion time is:

If the probability of success is .25,what is the probability of obtaining the first success within the first three trials?

Which model best describes the number of births in a hospital until the first twins are delivered?

For which binomial distribution would a Poisson approximation not be acceptable?

The coefficient of variation for a Poisson distribution with λ = 5 is:

The number of people injured in rafting expeditions on the Colorado River on a randomly chosen Thursday in August is best described by which model?

If X is a discrete uniform random variable ranging from 0 to 12,find P(X ≥ 10).

An example of a geometric random variable is the number of pine trees with pine beetle infestation in a random sample of 15 pine trees in Colorado.

Which of the following characterizes a Bernoulli process?

On a Sunday in April,dog bite victims arrive at Carver Memorial Hospital at a historical rate of 0.6 victim per day.On a given Sunday in April,what is the probability that exactly two dog bite victims will arrive?

The probability that a certain daily flight's departure from ORD to LAX is delayed is .02.Over six months,this flight departs 180 times.What is the approximate Poisson probability that it will be delayed fewer than 2 times?

The Poisson distribution describes the number of occurrences within a randomly chosen unit of time or space.

If 90 percent of automobiles in Orange County have both headlights working,what is the probability that in a sample of eight automobiles,at least seven will have both headlights working?

A stock portfolio consists of two stocks X and Y.Their daily closing prices are correlated random variables with variances σ_X² = 3.51 and σ_Y² = 5.22,and covariance σ_XY = -1.55.What is the standard deviation of the sum of the closing prices of these two stocks?

Cars are arriving at a toll booth at a rate of four per minute.What is the probability that exactly eight cars will arrive in the next two minutes?

The hypergeometric distribution is skewed right.

Overview of Statistics

Data Collection

Describing Data Visually

Descriptive Statistics

Probability

Continuous Probability Distributions

Sampling Distributions and Estimation

One-Sample Hypothesis Tests

Two-Sample Hypothesis Tests

Analysis of Variance

Simple Regression

Multiple Regression

Time-Series Analysis

Chi-Square Tests

Nonparametric Tests

Quality Management

Filters

Exam 6: Discrete Probability Distributions

Customer arrivals per unit of time would tend to follow a binomial distribution.

On Saturday morning,calls arrive at TicketMaster at a rate of 108 calls per hour.What is the probability of fewer than three calls in a randomly chosen minute?

Arrival of cars per minute at a toll booth may be characterized by the Poisson distribution if:

A project has three independent stages that must be completed in sequence.The time to complete each stage is a random variable.The expected times to complete the stages are μ1 = 23,μ2 = 11,μ3 = 17.The expected project completion time is:

If the probability of success is .25,what is the probability of obtaining the first success within the first three trials?

Which model best describes the number of births in a hospital until the first twins are delivered?

For which binomial distribution would a Poisson approximation not be acceptable?

The coefficient of variation for a Poisson distribution with λ = 5 is:

The number of people injured in rafting expeditions on the Colorado River on a randomly chosen Thursday in August is best described by which model?

If X is a discrete uniform random variable ranging from 0 to 12,find P(X ≥ 10).

An example of a geometric random variable is the number of pine trees with pine beetle infestation in a random sample of 15 pine trees in Colorado.

Which of the following characterizes a Bernoulli process?

On a Sunday in April,dog bite victims arrive at Carver Memorial Hospital at a historical rate of 0.6 victim per day.On a given Sunday in April,what is the probability that exactly two dog bite victims will arrive?

The probability that a certain daily flight's departure from ORD to LAX is delayed is .02.Over six months,this flight departs 180 times.What is the approximate Poisson probability that it will be delayed fewer than 2 times?

The Poisson distribution describes the number of occurrences within a randomly chosen unit of time or space.

If 90 percent of automobiles in Orange County have both headlights working,what is the probability that in a sample of eight automobiles,at least seven will have both headlights working?

A stock portfolio consists of two stocks X and Y.Their daily closing prices are correlated random variables with variances σX2 = 3.51 and σY2 = 5.22,and covariance σXY = -1.55.What is the standard deviation of the sum of the closing prices of these two stocks?

Cars are arriving at a toll booth at a rate of four per minute.What is the probability that exactly eight cars will arrive in the next two minutes?

The hypergeometric distribution is skewed right.

Overview of Statistics

Data Collection

Describing Data Visually

Descriptive Statistics

Probability

Continuous Probability Distributions

Sampling Distributions and Estimation

One-Sample Hypothesis Tests

Two-Sample Hypothesis Tests

Analysis of Variance

Simple Regression

Multiple Regression

Time-Series Analysis

Chi-Square Tests

Nonparametric Tests

Quality Management

Filters

A project has three independent stages that must be completed in sequence.The time to complete each stage is a random variable.The expected times to complete the stages are μ₁ = 23,μ₂ = 11,μ₃ = 17.The expected project completion time is:

A stock portfolio consists of two stocks X and Y.Their daily closing prices are correlated random variables with variances σ_X² = 3.51 and σ_Y² = 5.22,and covariance σ_XY = -1.55.What is the standard deviation of the sum of the closing prices of these two stocks?