Question 1

The hypergeometric probability distribution can be approximated by the Poisson distribution.

Accepted Answer

A) True 
 B)False

Question 2

A random variable that is defined to be the total number of successes in n trials is a __________ random variable.

Accepted Answer

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

Question 3

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

Accepted Answer

A) True 
 B)False

Question 4

Which one of the following statements is not an assumption of the binomial distribution?

Accepted Answer

A)  Sampling is with replacement. 
B)  The experiment consists of n identical trials. 
C)  The probability of success remains constant from trial to trial. 
D)  Trials are independent of each other. 
E)  Each trial results in one of two mutually exclusive outcomes. 
A)  Sampling is with replacement. 
B)  The experiment consists of n identical trials. 
C)  The probability of success remains constant from trial to trial. 
D)  Trials are independent of each other. 
E)  Each trial results in one of two mutually exclusive outcomes.

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 only 1 supports increased spending on environmental issues.

Accepted Answer

A)  .0330 
B)  .1318 
C)  .3560 
D)  .7844 
A)  .0330 
B)  .1318 
C)  .3560 
D)  .7844

Question 6

The J.O.Supplies Company buys calculators from a non-US supplier.The probability of a defective calculator is 10 percent.If 100 calculators are selected at random,what is the expected number of defectives?

Accepted Answer

A)  9 
B)  90 
C)  10 
D)  95 
A)  9 
B)  90 
C)  10 
D)  95

Question 7

If the number of surface nonconformities on a specific size of a 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 nonconformities is most likely given by the binomial distribution.

Accepted Answer

A) True 
 B)False

Question 8

The mean of the binomial distribution is np(1 − p).

Accepted Answer

A) True 
 B)False

Question 9

The manager of the local grocery store has determined that,on average,4 customers use the service desk every half-hour.Assume that the number of customers using the service desk has a Poisson distribution.What is the probability that during a randomly selected half-hour period,no more than 2 customers use the service desk?

Accepted Answer

A)  .2381 
B)  .1465 
C)  .7619 
D)  .8535 
E)  .0916 
A)  .2381 
B)  .1465 
C)  .7619 
D)  .8535 
E)  .0916

Question 10

For a discrete probability distribution,the value of p(x)for each value of x falls between −1 and 1.

Accepted Answer

A) True 
 B)False

Question 11

A total of 50 raffle tickets are sold for a contest to win a car.If you purchase one ticket,what are your odds against winning?

Accepted Answer

A)  49 to 1 
B)  50 to 1 
C)  .05 
D)  .01 
A)  49 to 1 
B)  50 to 1 
C)  .05 
D)  .01

Question 12

Depending on the mean of the Poisson distribution,the distribution can either be very skewed to the right or quite symmetrical.

Accepted Answer

A) True 
 B)False

Question 13

With two random variables x and y,a positive covariance says that as x increases,y tends to increase in a linear fashion.

Accepted Answer

A) True 
 B)False

Question 14

The probability that a given computer chip will fail is 0.02.Find the probability that of 5 delivered chips,exactly 2 will fail.

Accepted Answer

A)  .9039 
B)  .0922 
C)  .0038 
D)  .0000 
A)  .9039 
B)  .0922 
C)  .0038 
D)  .0000

Question 15

The Securities and Exchange Commission has determined that the number of companies listed on the NYSE declaring bankruptcy is approximately a Poisson distribution with a mean of 2.6 per month.Find the probability that exactly 4 bankruptcies occur next month.

Accepted Answer

A)  .8774 
B)  .1414 
C)  .1557 
D)  .2176 
A)  .8774 
B)  .1414 
C)  .1557 
D)  .2176

Question 16

The property of expected values says if a and b are constants,and if x and y are random variables,then μ(ax +by) = aμx + bμy + 2ab.

Accepted Answer

A) True 
 B)False

Question 17

The binomial experiment consists of n independent,identical trials,each of which results in either success or failure and is such that the probability of success on any trial is the same.

Accepted Answer

A) True 
 B)False

Question 18

A multiple-choice test has 30 questions and each one has five possible answers,of which only one is correct.If all answers were guesses,find the probability of getting exactly four correct answers.

Accepted Answer

A)  .0604 
B)  .1325 
C)  .2552 
D)  .8000 
A)  .0604 
B)  .1325 
C)  .2552 
D)  .8000

Question 19

In the context of the hypergeometric distribution,r is

Accepted Answer

A)  sample size. 
B)  the number of items in the population that are successes. 
C)  the number of items that are sampled without replacement. 
D)  the number of items in the sample that are successes. 
A)  sample size. 
B)  the number of items in the population that are successes. 
C)  the number of items that are sampled without replacement. 
D)  the number of items in the sample that are successes.

Question 20

If x is a binomial random variable,then the standard deviation of x is given by

Accepted Answer

A)  np. 
B)  (npq)2. 
C)  √npq. 
D)  npq. 
A)  np. 
B)  (npq)2. 
C)  √npq. 
D)  npq.

The hypergeometric probability distribution can be approximated by the Poisson distribution.

A random variable that is defined to be the total number of successes in n trials is a __________ random variable.

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

Which one of the following statements is not an assumption of the binomial distribution?

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 only 1 supports increased spending on environmental issues.

The J.O.Supplies Company buys calculators from a non-US supplier.The probability of a defective calculator is 10 percent.If 100 calculators are selected at random,what is the expected number of defectives?

The mean of the binomial distribution is np(1 − p).

For a discrete probability distribution,the value of p(x)for each value of x falls between −1 and 1.

A total of 50 raffle tickets are sold for a contest to win a car.If you purchase one ticket,what are your odds against winning?

Depending on the mean of the Poisson distribution,the distribution can either be very skewed to the right or quite symmetrical.

With two random variables x and y,a positive covariance says that as x increases,y tends to increase in a linear fashion.

The probability that a given computer chip will fail is 0.02.Find the probability that of 5 delivered chips,exactly 2 will fail.

The Securities and Exchange Commission has determined that the number of companies listed on the NYSE declaring bankruptcy is approximately a Poisson distribution with a mean of 2.6 per month.Find the probability that exactly 4 bankruptcies occur next month.

The property of expected values says if a and b are constants,and if x and y are random variables,then μ₍_ax₊_by₎ = aμ_x + bμ_y + 2ab.

The binomial experiment consists of n independent,identical trials,each of which results in either success or failure and is such that the probability of success on any trial is the same.

A multiple-choice test has 30 questions and each one has five possible answers,of which only one is correct.If all answers were guesses,find the probability of getting exactly four correct answers.

In the context of the hypergeometric distribution,r is

If x is a binomial random variable,then the standard deviation of x is given by

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 hypergeometric probability distribution can be approximated by the Poisson distribution.

A random variable that is defined to be the total number of successes in n trials is a __________ random variable.

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

Which one of the following statements is not an assumption of the binomial distribution?

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 only 1 supports increased spending on environmental issues.

The J.O.Supplies Company buys calculators from a non-US supplier.The probability of a defective calculator is 10 percent.If 100 calculators are selected at random,what is the expected number of defectives?

The mean of the binomial distribution is np(1 − p).

For a discrete probability distribution,the value of p(x)for each value of x falls between −1 and 1.

A total of 50 raffle tickets are sold for a contest to win a car.If you purchase one ticket,what are your odds against winning?

Depending on the mean of the Poisson distribution,the distribution can either be very skewed to the right or quite symmetrical.

With two random variables x and y,a positive covariance says that as x increases,y tends to increase in a linear fashion.

The probability that a given computer chip will fail is 0.02.Find the probability that of 5 delivered chips,exactly 2 will fail.

The Securities and Exchange Commission has determined that the number of companies listed on the NYSE declaring bankruptcy is approximately a Poisson distribution with a mean of 2.6 per month.Find the probability that exactly 4 bankruptcies occur next month.

The property of expected values says if a and b are constants,and if x and y are random variables,then μ(ax +by) = aμx + bμy + 2ab.

The binomial experiment consists of n independent,identical trials,each of which results in either success or failure and is such that the probability of success on any trial is the same.

A multiple-choice test has 30 questions and each one has five possible answers,of which only one is correct.If all answers were guesses,find the probability of getting exactly four correct answers.

In the context of the hypergeometric distribution,r is

If x is a binomial random variable,then the standard deviation of x is given by

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

The property of expected values says if a and b are constants,and if x and y are random variables,then μ₍_ax₊_by₎ = aμ_x + bμ_y + 2ab.