Question 1

A hypergeometric random variable x has a distribution that is approximated by a binomial distribution when:

Accepted Answer

A) The number of successes is larger than the number of failures in the population. 
B) A sample is selected from the population without replacement. 
C) The population is much larger than the sample size. 
D) The sample size is half the size of the original population. 
A) The number of successes is larger than the number of failures in the population. 
B) A sample is selected from the population without replacement. 
C) The population is much larger than the sample size. 
D) The sample size is half the size of the original population.

Question 2

For a binomial process,the probability of success is 40 percent and the number of trials is 5.Find P(X ≤ 1).

Accepted Answer

A) .0870 
B) .2592 
C) .0778 
D) .3370 
A) .0870 
B) .2592 
C) .0778 
D) .3370

Question 3

X has the probability distribution:   Compute the expected value of X.

Accepted Answer

A) 1.3 
B) 1.0 
C) 2.4 
D) 1.8 
A) 1.3 
B) 1.0 
C) 2.4 
D) 1.8

Question 4

Consider a Poisson distribution with an average of 3 customers per minute at the local grocery store.Determine the expected number of customer arrivals for a five-minute period.

Accepted Answer

A) 15 
B) 3 
C) 243 
D) 125 
A) 15 
B) 3 
C) 243 
D) 125

Question 5

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 6

Suppose you randomly select 3 DVDs from a production run of 10.Of the 10 DVDs,9 are expected to last a minimum of 3 years.What is the standard deviation of the random variable x?

Accepted Answer

The answer of Suppose you randomly select 3 DVDs from...

Question 7

If the probability distribution of X is:   What is the expected value of X?

Accepted Answer

A) 1.0 
B) 5.0 
C) 2.25 
D) 2.24 
A) 1.0 
B) 5.0 
C) 2.25 
D) 2.24

Question 8

A correlation coefficient is a unitless measure of the linear relationship between two random variables.

Accepted Answer

A) True 
 B)False

Question 9

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 10

Determine the probability that a 3 will appear twice,if a fair die is rolled 10 times.

Accepted Answer

A) .5010 
B) .2907 
C) .2318 
D) .0065 
A) .5010 
B) .2907 
C) .2318 
D) .0065

Question 11

According to data from the state blood program,40 percent of all individuals have group A blood.If six individuals give blood,find the probability that exactly three of the individuals have group A blood.

Accepted Answer

A) .4000 
B) .2765 
C) .5875 
D) .0041 
A) .4000 
B) .2765 
C) .5875 
D) .0041

Question 12

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

Accepted Answer

A) True 
 B)False

Question 13

The time (in seconds)it takes for an athlete to run 50 meters is an example of a continuous random variable.

Accepted Answer

A) True 
 B)False

Question 14

In a study conducted for the state Department of Education,30 percent of the teachers who left teaching did so because they were laid off.Assume that we randomly select 10 teachers who have recently left their profession.Find the probability that exactly 4 of them were laid off.

Accepted Answer

A) .3000 
B) .2668 
C) .2001 
D) .0090 
A) .3000 
B) .2668 
C) .2001 
D) .0090

Question 15

An important part of the customer service responsibilities of a cable company relates to the speed with which trouble in service can be repaired.Historically,the data show that the likelihood is 0.75 that troubles in a residential service can be repaired on the same day.For the first five troubles reported on a given day,what is the probability that all five will be repaired on the same day?

Accepted Answer

A) .0010 
B) .6328 
C) .9990 
D) .2373 
A) .0010 
B) .6328 
C) .9990 
D) .2373

Question 16

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 17

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 18

Assume the number of trucks passing an intersection has a Poisson distribution with a mean of 5 trucks per minute.What is the probability of 0 or 1 trucks in one minute?

Accepted Answer

A) .0404 
B) .0337 
C) .0842 
D) .0067 
A) .0404 
B) .0337 
C) .0842 
D) .0067

Question 19

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 20

If n = 15 and p = .4,then the standard deviation of the binomial distribution is:

Accepted Answer

A) 9 
B) 6 
C) 3.6 
D) 1.897 
E) .4 
A) 9 
B) 6 
C) 3.6 
D) 1.897 
E) .4

A hypergeometric random variable x has a distribution that is approximated by a binomial distribution when:

For a binomial process,the probability of success is 40 percent and the number of trials is 5.Find P(X ≤ 1).

X has the probability distribution: Compute the expected value of X.

Consider a Poisson distribution with an average of 3 customers per minute at the local grocery store.Determine the expected number of customer arrivals for a five-minute period.

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

Suppose you randomly select 3 DVDs from a production run of 10.Of the 10 DVDs,9 are expected to last a minimum of 3 years.What is the standard deviation of the random variable x?

If the probability distribution of X is: What is the expected value of X?

A correlation coefficient is a unitless measure of the linear relationship between two random variables.

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?

Determine the probability that a 3 will appear twice,if a fair die is rolled 10 times.

According to data from the state blood program,40 percent of all individuals have group A blood.If six individuals give blood,find the probability that exactly three of the individuals have group A blood.

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

The time (in seconds)it takes for an athlete to run 50 meters is an example of a continuous random variable.

In a study conducted for the state Department of Education,30 percent of the teachers who left teaching did so because they were laid off.Assume that we randomly select 10 teachers who have recently left their profession.Find the probability that exactly 4 of them were laid off.

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?

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

Assume the number of trucks passing an intersection has a Poisson distribution with a mean of 5 trucks per minute.What is the probability of 0 or 1 trucks in one minute?

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.

If n = 15 and p = .4,then the standard deviation of the binomial distribution is:

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 Based on Two Samples

Experimental Design and Analysis of Variance

Chi-Square Tests

Simple Linear Regression Analysis

Multiple Regression and Model Building

Process Improvement Using Control Charts

Filters

Exam 5: Discrete Random Variables

A hypergeometric random variable x has a distribution that is approximated by a binomial distribution when:

For a binomial process,the probability of success is 40 percent and the number of trials is 5.Find P(X ≤ 1).

X has the probability distribution: Compute the expected value of X.

Consider a Poisson distribution with an average of 3 customers per minute at the local grocery store.Determine the expected number of customer arrivals for a five-minute period.

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

Suppose you randomly select 3 DVDs from a production run of 10.Of the 10 DVDs,9 are expected to last a minimum of 3 years.What is the standard deviation of the random variable x?

If the probability distribution of X is: What is the expected value of X?

A correlation coefficient is a unitless measure of the linear relationship between two random variables.

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?

Determine the probability that a 3 will appear twice,if a fair die is rolled 10 times.

According to data from the state blood program,40 percent of all individuals have group A blood.If six individuals give blood,find the probability that exactly three of the individuals have group A blood.

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

The time (in seconds)it takes for an athlete to run 50 meters is an example of a continuous random variable.

In a study conducted for the state Department of Education,30 percent of the teachers who left teaching did so because they were laid off.Assume that we randomly select 10 teachers who have recently left their profession.Find the probability that exactly 4 of them were laid off.

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?

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

Assume the number of trucks passing an intersection has a Poisson distribution with a mean of 5 trucks per minute.What is the probability of 0 or 1 trucks in one minute?

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.

If n = 15 and p = .4,then the standard deviation of the binomial distribution is:

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 Based on Two Samples

Experimental Design and Analysis of Variance

Chi-Square Tests

Simple Linear Regression Analysis

Multiple Regression and Model Building

Process Improvement Using Control Charts

Filters