Question 1

A Poisson random variable counts the number of successes (occurrences of a certain event)over a given interval of time or space.

Accepted Answer

A) True 
 B)False

Question 2

The ounces of soda consumed by an adult next month are an example of a discrete random variable.

Accepted Answer

A) True 
 B)False

Question 3

A professor has learned that three students in his class of 20 will cheat on the final exam.He decides to focus his attention on four randomly chosen students during the exam.What is the probability that he finds at least one of the students cheating?

Accepted Answer

A)  0.4912 
B)  0.4211 
C)  0.5088 
D)  0.5789 
A)  0.4912 
B)  0.4211 
C)  0.5088 
D)  0.5789

Question 4

Consider the following discrete probability distribution.   What is the probability that X is less than 5?

Accepted Answer

A)  0.10 
B)  0.15 
C)  0.35 
D)  0.45 
A)  0.10 
B)  0.15 
C)  0.35 
D)  0.45

Question 5

Lisa is in a free-throw shooting contest where each contestant attempts 10 free throws.On average,Lisa makes 77% of the free throws she attempts.
a.What is the probability that she makes exactly eight free throws?
b.What is the probability she makes at least nine free throws?
c.What is the probability she makes fewer than nine free throws?
d.Lisa is competing against Bill to see who can make the most free throws in 10 attempts.Suppose Bill goes first and makes seven.Should we expect Lisa to make at least as many as Bill? Explain.

Accepted Answer

For a binomial random variable X,the pro

Question 6

Consider the following probability distribution.   The standard deviation is _________.

Accepted Answer

A)  0.89 
B)  0.94 
C)  1.65 
D)  1.90 
A)  0.89 
B)  0.94 
C)  1.65 
D)  1.90

Question 7

A car salesperson has a 5% chance of landing a sale with a random customer on the lot.Suppose 10 people come onto the lot today.
a.What is the probability that the salesperson sells exactly three cars today?
b.What is the probability he or she sells fewer than two cars today?
c.What is the expected number of cars he or she is going to sell today?

Accepted Answer

For a binomial random variable X,the pro

Question 8

The number of cars sold by a car salesperson during each of the last 25 weeks is the following:   What is the expected number of cars sold by the salesperson during a week?

Accepted Answer

A)  0 
B)  0.8 
C)  1 
D)  1.5 
A)  0 
B)  0.8 
C)  1 
D)  1.5

Question 9

A roll of steel is manufactured on a processing line.The anticipated number of defects in a 10-foot segment of this roll is two.What is the probability of no defects in 10 feet of steel?

Accepted Answer

A)  0.0002 
B)  0.1353 
C)  0.1804 
D)  0.8647 
A)  0.0002 
B)  0.1353 
C)  0.1804 
D)  0.8647

Question 10

Consider the following discrete probability distribution.   What is the probability that X is 0?

Accepted Answer

A)  0.10 
B)  0.35 
C)  0.55 
D)  0.65 
A)  0.10 
B)  0.35 
C)  0.55 
D)  0.65

Question 11

The number of cars sold by a car salesperson during each of the last 25 weeks is the following:   What is the probability that the salesperson will sell one car during a week?

Accepted Answer

A)  0.20 
B)  0.40 
C)  0.60 
D)  0.80 
A)  0.20 
B)  0.40 
C)  0.60 
D)  0.80

Question 12

An analyst estimates that a stock has the following probabilities of year-end prices.   a.Calculate the expected price at year-end.
b.Calculate the variance and the standard deviation.

Accepted Answer

The expected value of X is calculated as

Question 13

Given two random variables X and Y,the expected value of their sum,E(X + Y),is equal to the sum of their individual expected values,E (X)and E (Y).

Accepted Answer

A) True 
 B)False

Question 14

The number of homes sold by a realtor during a month has the following probability distribution:   What is the probability that the realtor sells no more than one house during a month?

Accepted Answer

A)  0.20 
B)  0.40 
C)  0.60 
D)  0.80 
A)  0.20 
B)  0.40 
C)  0.60 
D)  0.80

Question 15

Thirty percent of the CFA candidates have a degree in economics.A random sample of three CFA candidates is selected.What is the probability that none of them has a degree in economics?

Accepted Answer

A)  0.027 
B)  0.300 
C)  0.343 
D)  0.900 
A)  0.027 
B)  0.300 
C)  0.343 
D)  0.900

Question 16

A bank manager estimates that an average of two customers enters the tellers' queue every five minutes.Assume that the number of customers that enters the tellers' queue is Poisson distributed.What is the probability that fewer than two customers enter the queue in a randomly selected five-minute period?

Accepted Answer

A)  0.1353 
B)  0.2707 
C)  0.4060 
D)  0.6767 
A)  0.1353 
B)  0.2707 
C)  0.4060 
D)  0.6767

Question 17

Which of the following can be represented by a discrete random variable?

Accepted Answer

A)  The number of obtained spots when rolling a six-sided die 
B)  The height of college students 
C)  The average outside temperature taken every day for two weeks 
D)  The finishing time of participants in a cross-country meet 
A)  The number of obtained spots when rolling a six-sided die 
B)  The height of college students 
C)  The average outside temperature taken every day for two weeks 
D)  The finishing time of participants in a cross-country meet

Question 18

Does the following table describe a discrete probability distribution?

Accepted Answer

The two properties that must be met for

Question 19

An analyst has constructed the following probability distribution for firm X's predicted return for the upcoming year.   The expected value and the variance of this distribution are _____ and _____. Expected Value Variance

Accepted Answer

A)  1 4.58 
B)  2 21.00 
C)  2.5 4.58 
D)  2.5 21.00 
A)  1 4.58 
B)  2 21.00 
C)  2.5 4.58 
D)  2.5 21.00

Question 20

A bank manager estimates that an average of two customers enters the tellers' queue every five minutes.Assume that the number of customers that enters the tellers' queue is Poisson distributed.What is the probability that exactly seven customers enter the queue in a randomly selected 15-minute period?

Accepted Answer

A)  0.0034 
B)  0.1033 
C)  0.1377 
D)  0.1606 
A)  0.0034 
B)  0.1033 
C)  0.1377 
D)  0.1606

A Poisson random variable counts the number of successes (occurrences of a certain event)over a given interval of time or space.

The ounces of soda consumed by an adult next month are an example of a discrete random variable.

A professor has learned that three students in his class of 20 will cheat on the final exam.He decides to focus his attention on four randomly chosen students during the exam.What is the probability that he finds at least one of the students cheating?

Consider the following discrete probability distribution. What is the probability that X is less than 5?

Consider the following probability distribution. The standard deviation is _________.

The number of cars sold by a car salesperson during each of the last 25 weeks is the following: What is the expected number of cars sold by the salesperson during a week?

A roll of steel is manufactured on a processing line.The anticipated number of defects in a 10-foot segment of this roll is two.What is the probability of no defects in 10 feet of steel?

Consider the following discrete probability distribution. What is the probability that X is 0?

The number of cars sold by a car salesperson during each of the last 25 weeks is the following: What is the probability that the salesperson will sell one car during a week?

An analyst estimates that a stock has the following probabilities of year-end prices. a.Calculate the expected price at year-end. b.Calculate the variance and the standard deviation.

Given two random variables X and Y,the expected value of their sum,E(X + Y),is equal to the sum of their individual expected values,E (X)and E (Y).

The number of homes sold by a realtor during a month has the following probability distribution: What is the probability that the realtor sells no more than one house during a month?

Thirty percent of the CFA candidates have a degree in economics.A random sample of three CFA candidates is selected.What is the probability that none of them has a degree in economics?

Which of the following can be represented by a discrete random variable?

Does the following table describe a discrete probability distribution?

An analyst has constructed the following probability distribution for firm X's predicted return for the upcoming year. The expected value and the variance of this distribution are _ and _. Expected Value Variance

Statistics and Data

Tabular and Graphical Methods

Numerical Descriptive Measures

Basic Probability Concepts

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Testing

Statistical Inference Concerning Two Populations

Statistical Inference Concerning Variance

Chi-Square Tests

Analysis of Variance

Regression Analysis

Inference With Regression Models

Regression Models for Nonlinear Relationships

Regression Models With Dummy Variables

Time Series and Forecasting

Returns, Index Numbers and Inflation

Nonparametric Tests

Filters

Exam 5: Discrete Probability Distributions

A Poisson random variable counts the number of successes (occurrences of a certain event)over a given interval of time or space.

The ounces of soda consumed by an adult next month are an example of a discrete random variable.

A professor has learned that three students in his class of 20 will cheat on the final exam.He decides to focus his attention on four randomly chosen students during the exam.What is the probability that he finds at least one of the students cheating?

Consider the following discrete probability distribution. What is the probability that X is less than 5?

Consider the following probability distribution. The standard deviation is _________.

The number of cars sold by a car salesperson during each of the last 25 weeks is the following: What is the expected number of cars sold by the salesperson during a week?

A roll of steel is manufactured on a processing line.The anticipated number of defects in a 10-foot segment of this roll is two.What is the probability of no defects in 10 feet of steel?

Consider the following discrete probability distribution. What is the probability that X is 0?

The number of cars sold by a car salesperson during each of the last 25 weeks is the following: What is the probability that the salesperson will sell one car during a week?

An analyst estimates that a stock has the following probabilities of year-end prices. a.Calculate the expected price at year-end. b.Calculate the variance and the standard deviation.

Given two random variables X and Y,the expected value of their sum,E(X + Y),is equal to the sum of their individual expected values,E (X)and E (Y).

The number of homes sold by a realtor during a month has the following probability distribution: What is the probability that the realtor sells no more than one house during a month?

Thirty percent of the CFA candidates have a degree in economics.A random sample of three CFA candidates is selected.What is the probability that none of them has a degree in economics?

Which of the following can be represented by a discrete random variable?

Does the following table describe a discrete probability distribution?

An analyst has constructed the following probability distribution for firm X's predicted return for the upcoming year. The expected value and the variance of this distribution are _____ and _____. Expected Value Variance

Statistics and Data

Tabular and Graphical Methods

Numerical Descriptive Measures

Basic Probability Concepts

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Testing

Statistical Inference Concerning Two Populations

Statistical Inference Concerning Variance

Chi-Square Tests

Analysis of Variance

Regression Analysis

Inference With Regression Models

Regression Models for Nonlinear Relationships

Regression Models With Dummy Variables

Time Series and Forecasting

Returns, Index Numbers and Inflation

Nonparametric Tests

Filters

An analyst has constructed the following probability distribution for firm X's predicted return for the upcoming year. The expected value and the variance of this distribution are _ and _. Expected Value Variance