Question 1

Which one of the following probability distributions represents the random variable "the number of 6's that appear in a roll of two fair dice"?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 2

It is reported that 23% of the home mortgages in Cowlitz County are "underwater".For 50 randomly selected home mortgages, compute the variance of the random variable "number of underwater mortgages."

Accepted Answer

A) 9.12 
B) 8.86 
C) 16.23 
D) 12.47 
E) 11.58 
A) 9.12 
B) 8.86 
C) 16.23 
D) 12.47 
E) 11.58

Question 3

The of a binomial distribution is equal to n time p.

Accepted Answer

A) expected value 
B) variance 
C) standard deviation 
D) probability of success 
E) the number of trials 
A) expected value 
B) variance 
C) standard deviation 
D) probability of success 
E) the number of trials

Question 4

Julian picks winning and losing stocks by tossing a coin (heads means winner, tails means loser).To test his 'system', his friend gives him a list of 20 stocks, half of which doubled in value over the past 3 years (winners) and half of which lost half their value over the past 3 years (losers).How likely is it that Julian properly classifies at least 80% of the stocks on the list?

Accepted Answer

A) .0201 
B) .0059 
C) .1201 
D) .0952 
E) .1028 
A) .0201 
B) .0059 
C) .1201 
D) .0952 
E) .1028

Question 5

An experiment consists of making 80 telephone calls in order to sell a particular insurance policy.The random variable is the number of sales made.This random variable is a:

Accepted Answer

A) a discrete random variable 
B) a continuous random variable 
C) either a continuous or a discrete random variable, depending on the number of the calls made 
D) either a continuous or a discrete random variable, depending on the gender of the customers 
E) a complex random variable 
A) a discrete random variable 
B) a continuous random variable 
C) either a continuous or a discrete random variable, depending on the number of the calls made 
D) either a continuous or a discrete random variable, depending on the gender of the customers 
E) a complex random variable

Question 6

The most popular names for babies born in the United Kingdom in 2012 were Harry and Amelia.Of the roughly 400,000 baby boys born in the UK in 2012, two percent were named Harry.Two percent of girls born in the UK in 2012 were named Amelia (Source: UK Office for National Statistics, Baby Names, England and Wales, 2012).If thirty boys are selected at random from those born in the UK in 2012, what is the probability that two boys or more in the group will be named Harry?

Accepted Answer

A) 9.9% 
B) 12.1% 
C) 54.5% 
D) 87.9% 
E) 93.2% 
A) 9.9% 
B) 12.1% 
C) 54.5% 
D) 87.9% 
E) 93.2%

Question 7

Julian picks winning and losing stocks by tossing a coin (heads means winner, tails means loser).To test his 'system', his friend gives him a list of 20 stocks, half of which doubled in value over the past 3 years (winners) and half of which lost half their value over the past 3 years (losers).How likely is it that Julian properly classifies at least 60% of the stocks on the list?

Accepted Answer

A) .2202 
B) .1786 
C) .1365 
D) .1973 
E) .2517 
A) .2202 
B) .1786 
C) .1365 
D) .1973 
E) .2517

Question 8

Which of the following is NOT a condition of an experiment where the binomial probability distribution is applicable?

Accepted Answer

A) the experiment has a sequence of n identical trials 
B) exactly two outcomes are possible on each trial 
C) the trials are dependent 
D) the probabilities of the outcomes do not change from one trial to another 
E) all are characteristics of a binomial probability experiment 
A) the experiment has a sequence of n identical trials 
B) exactly two outcomes are possible on each trial 
C) the trials are dependent 
D) the probabilities of the outcomes do not change from one trial to another 
E) all are characteristics of a binomial probability experiment

Question 9

Ten percent of graduating college seniors report planning to spend at least one year volunteering for a charitable organization.You interview 30 randomly selected graduating seniors.Assuming that all the binomial conditions are met, determine the probability that exactly one student in this group of 30 plans to volunteer.

Accepted Answer

A) .2234 
B) .1775 
C) .1612 
D) .1413 
E) .2972 
A) .2234 
B) .1775 
C) .1612 
D) .1413 
E) .2972

Question 10

The variance of a binomial random variable X with n trials and p probability of success, where p is greater than 0,

Accepted Answer

A) will always be less than the expected value of X. 
B) will always be equal to the expected value of X. 
C) will always be greater than the expected value of X. 
D) may be less than, equal to, or greater than the expected value of X. 
E) has no relationship to the expected value of X. 
A) will always be less than the expected value of X. 
B) will always be equal to the expected value of X. 
C) will always be greater than the expected value of X. 
D) may be less than, equal to, or greater than the expected value of X. 
E) has no relationship to the expected value of X.

Question 11

During the summer season, the average number of lightning strikes per week in the Royal Canyon area is 3.6.Assume that all the Poisson conditions are met.Let x represent values for the random variable "number of lightning strikes in a week." What is the standard deviation of x?

Accepted Answer

A) 1.897 
B) 2.354 
C) 4.162 
D) 1.212 
E) 1.318 
A) 1.897 
B) 2.354 
C) 4.162 
D) 1.212 
E) 1.318

Question 12

It is reported that 7% of the Super Star scratch-and-win lottery tickets are winners.If you scratch 250 tickets, what is the expected number of winners?

Accepted Answer

A) 19.8 
B) 22.6 
C) 17.5 
D) 27.4 
E) 29.1 
A) 19.8 
B) 22.6 
C) 17.5 
D) 27.4 
E) 29.1

Question 13

The expected value or mean of a Poisson distribution is the same as the variance.

Accepted Answer

A) True 
 B)False

Question 14

In a study of NBA basketball games, it was reported that there are, on average, .3 fouls committed per minute.Assume all the Poisson conditions are met.You are watching a game.Determine the probability of five fouls in the next 10-minute interval.

Accepted Answer

A) .1257 
B) .1008 
C) .2090 
D) .1368 
E) .1552 
A) .1257 
B) .1008 
C) .2090 
D) .1368 
E) .1552

Question 15

Salem University's MBA program has a 55% acceptance rate.You randomly select a sample of 20 applicants.For the random variable "number of applicants in the sample who are accepted into the program," compute the expected value.

Accepted Answer

A) 11 
B) 12.2 
C) 9.8 
D) 7.4 
E) 13.5 
A) 11 
B) 12.2 
C) 9.8 
D) 7.4 
E) 13.5

Question 16

The binomial probability for P(x < 2), where n = 18, p = .05 is .9418.If you use the Poisson distribution to approximate this binomial probability, what probability would you produce?

Accepted Answer

A) .7656 
B) .8146 
C) .9372 
D) .9514 
E) .9716 
A) .7656 
B) .8146 
C) .9372 
D) .9514 
E) .9716

Question 17

Salem University's MBA program has a 55% acceptance rate.If you randomly select a sample of 20 applicants, how likely is it that between 13 and 17 (inclusive) of the applicants will be accepted into the program?

Accepted Answer

A) .2989 
B) .3196 
C) .3341 
D) .2511 
E) .2813 
A) .2989 
B) .3196 
C) .3341 
D) .2511 
E) .2813

Question 18

Which graph below shows the shape of the Poisson distribution for λ = 5?

Accepted Answer

A) a 
B) b 
C) c 
D) d 
E) none of the above 
A) a 
B) b 
C) c 
D) d 
E) none of the above

Question 19

Ten percent of graduating college seniors report planning to spend at least one year volunteering for a charitable organization.You interview 30 randomly selected graduating seniors.Assuming that all the binomial conditions are met, determine the probability that no more than 4 students in the group plan to volunteer.

Accepted Answer

A) .7663 
B) .8598 
C) .8246 
D) .8916 
E) .9113 
A) .7663 
B) .8598 
C) .8246 
D) .8916 
E) .9113

Question 20

Below is a table showing the probability distribution for the random variable x.Compute the expected value of the random variable.

Accepted Answer

A) 36.4 
B) 35.0 
C) 32.9 
D) 41.3 
E) 38.0 
A) 36.4 
B) 35.0 
C) 32.9 
D) 41.3 
E) 38.0

Which one of the following probability distributions represents the random variable "the number of 6's that appear in a roll of two fair dice"?

It is reported that 23% of the home mortgages in Cowlitz County are "underwater".For 50 randomly selected home mortgages, compute the variance of the random variable "number of underwater mortgages."

The of a binomial distribution is equal to n time p.

An experiment consists of making 80 telephone calls in order to sell a particular insurance policy.The random variable is the number of sales made.This random variable is a:

Which of the following is NOT a condition of an experiment where the binomial probability distribution is applicable?

The variance of a binomial random variable X with n trials and p probability of success, where p is greater than 0,

During the summer season, the average number of lightning strikes per week in the Royal Canyon area is 3.6.Assume that all the Poisson conditions are met.Let x represent values for the random variable "number of lightning strikes in a week." What is the standard deviation of x?

It is reported that 7% of the Super Star scratch-and-win lottery tickets are winners.If you scratch 250 tickets, what is the expected number of winners?

The expected value or mean of a Poisson distribution is the same as the variance.

In a study of NBA basketball games, it was reported that there are, on average, .3 fouls committed per minute.Assume all the Poisson conditions are met.You are watching a game.Determine the probability of five fouls in the next 10-minute interval.

Salem University's MBA program has a 55% acceptance rate.You randomly select a sample of 20 applicants.For the random variable "number of applicants in the sample who are accepted into the program," compute the expected value.

The binomial probability for P(x < 2), where n = 18, p = .05 is .9418.If you use the Poisson distribution to approximate this binomial probability, what probability would you produce?

Salem University's MBA program has a 55% acceptance rate.If you randomly select a sample of 20 applicants, how likely is it that between 13 and 17 (inclusive) of the applicants will be accepted into the program?

Which graph below shows the shape of the Poisson distribution for λ = 5?

Below is a table showing the probability distribution for the random variable x.Compute the expected value of the random variable.

An Introduction to Statistics

Descriptive Statistics I: Elementary Data Presentation and Description

Descriptive Statistics II: Additional Descriptive Measures and Data Displays

Probability

Continuous Probability Distributions

Statistical Inference: Estimating a Population Mean

Interval Estimates for Proportions, Mean Differences and Proportion Differences

Statistical Hypothesis Testing: Hypothesis Tests for a Population Mean

Hypothesis Tests for Proportions, Mean Differences and Proportion Differences

Basic Regression Analysis

Multiple Regression

F Tests and Analysis of Variance

Experimental Designonline Only

Chi-Square Tests

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Exam 5: Discrete Probability Distributions

Which one of the following probability distributions represents the random variable "the number of 6's that appear in a roll of two fair dice"?

It is reported that 23% of the home mortgages in Cowlitz County are "underwater".For 50 randomly selected home mortgages, compute the variance of the random variable "number of underwater mortgages."

The of a binomial distribution is equal to n time p.

An experiment consists of making 80 telephone calls in order to sell a particular insurance policy.The random variable is the number of sales made.This random variable is a:

Which of the following is NOT a condition of an experiment where the binomial probability distribution is applicable?

The variance of a binomial random variable X with n trials and p probability of success, where p is greater than 0,

During the summer season, the average number of lightning strikes per week in the Royal Canyon area is 3.6.Assume that all the Poisson conditions are met.Let x represent values for the random variable "number of lightning strikes in a week." What is the standard deviation of x?

It is reported that 7% of the Super Star scratch-and-win lottery tickets are winners.If you scratch 250 tickets, what is the expected number of winners?

The expected value or mean of a Poisson distribution is the same as the variance.

In a study of NBA basketball games, it was reported that there are, on average, .3 fouls committed per minute.Assume all the Poisson conditions are met.You are watching a game.Determine the probability of five fouls in the next 10-minute interval.

Salem University's MBA program has a 55% acceptance rate.You randomly select a sample of 20 applicants.For the random variable "number of applicants in the sample who are accepted into the program," compute the expected value.

The binomial probability for P(x < 2), where n = 18, p = .05 is .9418.If you use the Poisson distribution to approximate this binomial probability, what probability would you produce?

Salem University's MBA program has a 55% acceptance rate.If you randomly select a sample of 20 applicants, how likely is it that between 13 and 17 (inclusive) of the applicants will be accepted into the program?

Which graph below shows the shape of the Poisson distribution for λ = 5?

Below is a table showing the probability distribution for the random variable x.Compute the expected value of the random variable.

An Introduction to Statistics

Descriptive Statistics I: Elementary Data Presentation and Description

Descriptive Statistics II: Additional Descriptive Measures and Data Displays

Probability

Continuous Probability Distributions

Statistical Inference: Estimating a Population Mean

Interval Estimates for Proportions, Mean Differences and Proportion Differences

Statistical Hypothesis Testing: Hypothesis Tests for a Population Mean

Hypothesis Tests for Proportions, Mean Differences and Proportion Differences

Basic Regression Analysis

Multiple Regression

F Tests and Analysis of Variance

Experimental Designonline Only

Chi-Square Tests

Filters