Question 1

The mean and the variance of a Poisson random variable are equal.

Accepted Answer

A) True 
 B)False

Question 2

A fair die is rolled 10 times.What is the probability that an odd number (1,3,or 5)will occur fewer than 3 times?

Accepted Answer

A)  .0547 
B)  .1172 
C)  .1550 
D)  .7752 
E)  .8450 
A)  .0547 
B)  .1172 
C)  .1550 
D)  .7752 
E)  .8450

Question 3

Two characteristics,or assumptions,of the Poisson distribution are that

Accepted Answer

A)  the probability of success remains constant from trial to trial,and the random variable of interest is continuous. 
B)  the event occurring in one interval is independent of the event occurring in any other nonoverlapping interval,and the random variable of interest is continuous. 
C)  the event occurring in one interval is independent of the event occurring in any other nonoverlapping interval,and the random variable of interest is discrete. 
D)  the event occurring in one interval is dependent on the event occurring in any other nonoverlapping interval,and the random variable of interest is continuous. 
A)  the probability of success remains constant from trial to trial,and the random variable of interest is continuous. 
B)  the event occurring in one interval is independent of the event occurring in any other nonoverlapping interval,and the random variable of interest is continuous. 
C)  the event occurring in one interval is independent of the event occurring in any other nonoverlapping interval,and the random variable of interest is discrete. 
D)  the event occurring in one interval is dependent on the event occurring in any other nonoverlapping interval,and the random variable of interest is continuous.

Question 4

A fair die is rolled 10 times.What is the average number of even number outcomes?

Accepted Answer

A)  3 
B)  4 
C)  5 
D)  6 
E)  7 
A)  3 
B)  4 
C)  5 
D)  6 
E)  7

Question 5

A study conducted by a local university found that 25 percent of college freshmen support increased spending on environmental issues.If 6 college freshmen are randomly selected,find the probability that fewer than 4 support increased spending on environmental issues.

Accepted Answer

A)  .0330 
B)  .7844 
C)  .9624 
D)  .9954 
A)  .0330 
B)  .7844 
C)  .9624 
D)  .9954

Question 6

The distribution whose mean is equal to its variance is the _________ distribution.

Accepted Answer

A)  binomial 
B)  Poisson 
C)  hypergeometric 
D)  continuous 
A)  binomial 
B)  Poisson 
C)  hypergeometric 
D)  continuous

Question 7

Which of the following distributions can be used to solve the following problem? The average number of cars arriving at a drive-through fast-food restaurant is three in 10 minutes.What is the probability that exactly four cars will arrive in a 5-minute interval?

Accepted Answer

A)  binomial 
B)  Poisson 
C)  both binomial and Poisson 
D)  neither binomial nor Poisson 
A)  binomial 
B)  Poisson 
C)  both binomial and Poisson 
D)  neither binomial nor Poisson

Question 8

The expected value of the discrete random variable x is the population mean.

Accepted Answer

A) True 
 B)False

Question 9

In the most recent election,19 percent of all eligible college students voted.If a random sample of 20 students were surveyed,find the probability that exactly half voted in the election.

Accepted Answer

A)  .0000 
B)  .0014 
C)  .0148 
D)  .4997 
A)  .0000 
B)  .0014 
C)  .0148 
D)  .4997

Question 10

The random variable x has a hypergeometric distribution,and the population contains 12 items.If you wanted to find the number of defects in a random sample of 3 selected items when the population contains 5 defects,identify the N,n,and r.

Accepted Answer

A)  N = 3,n = 12,r = 5 
B)  N = 5,n = 12,r = 7 
C)  N = 12,n = 5,r = 3 
D)  N = 12,n = 3,r = 5 
A)  N = 3,n = 12,r = 5 
B)  N = 5,n = 12,r = 7 
C)  N = 12,n = 5,r = 3 
D)  N = 12,n = 3,r = 5

Question 11

The mean of a hypergeometric random variable is defined as

Accepted Answer

A)  n × (r/N). 
B)  N × (r/n). 
C)  npq. 
D)  np. 
A)  n × (r/N). 
B)  N × (r/n). 
C)  npq. 
D)  np.

Question 12

A discrete random variable may assume a countable number of outcome values.

Accepted Answer

A) True 
 B)False

Question 13

If the number of surface nonconformities on a specific size of metal piece is the discrete random variable in question,then the appropriate probability distribution that can describe the probability of a specific size metal sheet containing 3 defects is given most likely by _________________ distribution(s).

Accepted Answer

A)  the binomial 
B)  the Poisson 
C)  the hypergeometric 
D)  both the binomial and Poisson 
A)  the binomial 
B)  the Poisson 
C)  the hypergeometric 
D)  both the binomial and Poisson

Question 14

The variable Employment Status,which can take either the value 1 for Employed and 0 for Unemployed,is an example of a _____________ random variable.

Accepted Answer

A)  Poisson 
B)  discrete 
C)  hypergeometric 
D)  continuous 
A)  Poisson 
B)  discrete 
C)  hypergeometric 
D)  continuous

Question 15

In a hypergeometric probability distribution of a population of N items,r refers to the number of successes and N − r to the number of failures.

Accepted Answer

A) True 
 B)False

Question 16

A discrete variable that can often be used to describe the number of occurrences of an event over a specified interval of time or space is a ___________ random variable.

Accepted Answer

A)  Poisson 
B)  discrete 
C)  hypergeometric 
D)  continuous 
A)  Poisson 
B)  discrete 
C)  hypergeometric 
D)  continuous

Question 17

The standard deviation of a discrete random variable measures the spread of the population of all possible values of x.

Accepted Answer

A) True 
 B)False

Question 18

In the most recent election,19 percent of all eligible college students voted.If a random sample of 20 students were surveyed,find the probability that none of the students voted.

Accepted Answer

A)  .0000 
B)  .0014 
C)  .0148 
D)  .4997 
A)  .0000 
B)  .0014 
C)  .0148 
D)  .4997

Question 19

The mean of the binomial distribution is equal to

Accepted Answer

A)  p. 
B)  np. 
C)  px(1 − p)n−x. 
D)  (n)(p)(1 − p). 
E)   
A)  p. 
B)  np. 
C)  px(1 − p)n−x. 
D)  (n)(p)(1 − p). 
E)

Question 20

For a random variable X,the mean value of the squared deviations of its values from their expected value is called its ____________.

Accepted Answer

A)  standard deviation 
B)  mean 
C)  probability 
D)  variance 
A)  standard deviation 
B)  mean 
C)  probability 
D)  variance

The mean and the variance of a Poisson random variable are equal.

A fair die is rolled 10 times.What is the probability that an odd number (1,3,or 5)will occur fewer than 3 times?

Two characteristics,or assumptions,of the Poisson distribution are that

A fair die is rolled 10 times.What is the average number of even number outcomes?

A study conducted by a local university found that 25 percent of college freshmen support increased spending on environmental issues.If 6 college freshmen are randomly selected,find the probability that fewer than 4 support increased spending on environmental issues.

The distribution whose mean is equal to its variance is the _________ distribution.

Which of the following distributions can be used to solve the following problem? The average number of cars arriving at a drive-through fast-food restaurant is three in 10 minutes.What is the probability that exactly four cars will arrive in a 5-minute interval?

The expected value of the discrete random variable x is the population mean.

In the most recent election,19 percent of all eligible college students voted.If a random sample of 20 students were surveyed,find the probability that exactly half voted in the election.

The random variable x has a hypergeometric distribution,and the population contains 12 items.If you wanted to find the number of defects in a random sample of 3 selected items when the population contains 5 defects,identify the N,n,and r.

The mean of a hypergeometric random variable is defined as

A discrete random variable may assume a countable number of outcome values.

The variable Employment Status,which can take either the value 1 for Employed and 0 for Unemployed,is an example of a _____________ random variable.

In a hypergeometric probability distribution of a population of N items,r refers to the number of successes and N − r to the number of failures.

A discrete variable that can often be used to describe the number of occurrences of an event over a specified interval of time or space is a ___________ random variable.

The standard deviation of a discrete random variable measures the spread of the population of all possible values of x.

In the most recent election,19 percent of all eligible college students voted.If a random sample of 20 students were surveyed,find the probability that none of the students voted.

The mean of the binomial distribution is equal to

For a random variable X,the mean value of the squared deviations of its values from their expected value is called its ____________.

An Introduction to Business Statistics

Descriptive Statistics: Tabular and Graphical Methods

Descriptive Statistics: Numerical Methods

Probability

Continuous Random Variables

Sampling and Sampling Distributions

Confidence Intervals

Hypothesis Testing

Statistical Inferences for Means and Proportions

Statistical Inferences for Population Variances

Experimental Design and Analysis of Variance

Chi-Square Tests

Simple Linear Regression Analysis

Multiple Regression and Model Building

Time Series Forecasting and Index Numbers

Nonparametric Methods

Decision Theory

Filters

Exam 5: Discrete Random Variables

The mean and the variance of a Poisson random variable are equal.

A fair die is rolled 10 times.What is the probability that an odd number (1,3,or 5)will occur fewer than 3 times?

Two characteristics,or assumptions,of the Poisson distribution are that

A fair die is rolled 10 times.What is the average number of even number outcomes?

A study conducted by a local university found that 25 percent of college freshmen support increased spending on environmental issues.If 6 college freshmen are randomly selected,find the probability that fewer than 4 support increased spending on environmental issues.

The distribution whose mean is equal to its variance is the _________ distribution.

Which of the following distributions can be used to solve the following problem? The average number of cars arriving at a drive-through fast-food restaurant is three in 10 minutes.What is the probability that exactly four cars will arrive in a 5-minute interval?

The expected value of the discrete random variable x is the population mean.

In the most recent election,19 percent of all eligible college students voted.If a random sample of 20 students were surveyed,find the probability that exactly half voted in the election.

The random variable x has a hypergeometric distribution,and the population contains 12 items.If you wanted to find the number of defects in a random sample of 3 selected items when the population contains 5 defects,identify the N,n,and r.

The mean of a hypergeometric random variable is defined as

A discrete random variable may assume a countable number of outcome values.

The variable Employment Status,which can take either the value 1 for Employed and 0 for Unemployed,is an example of a _____________ random variable.

In a hypergeometric probability distribution of a population of N items,r refers to the number of successes and N − r to the number of failures.

A discrete variable that can often be used to describe the number of occurrences of an event over a specified interval of time or space is a ___________ random variable.

The standard deviation of a discrete random variable measures the spread of the population of all possible values of x.

In the most recent election,19 percent of all eligible college students voted.If a random sample of 20 students were surveyed,find the probability that none of the students voted.

The mean of the binomial distribution is equal to

For a random variable X,the mean value of the squared deviations of its values from their expected value is called its ____________.

An Introduction to Business Statistics

Descriptive Statistics: Tabular and Graphical Methods

Descriptive Statistics: Numerical Methods

Probability

Continuous Random Variables

Sampling and Sampling Distributions

Confidence Intervals

Hypothesis Testing

Statistical Inferences for Means and Proportions

Statistical Inferences for Population Variances

Experimental Design and Analysis of Variance

Chi-Square Tests

Simple Linear Regression Analysis

Multiple Regression and Model Building

Time Series Forecasting and Index Numbers

Nonparametric Methods

Decision Theory

Filters